Reviewing Sex and the City: The Movie, film critic Mark Kermode said something very prescient amid the tumbling vitriol. Nobody does angry, exasperated disbelief quite like he does, but there was a weary resignation in his voice as he reasoned why people shouldn't bother watching it. "If you do, it'll only encourage them to make another." Lo and behold, two years later a sequel appeared that plumbed even greater depths and prompted yet more howls of anguish - "Ghastly, putrid, vomit-inducing" - at just how spectacularly bad it actually was.

Currently proving Kermode's theory is Sharknado 2: The Second One, the sequel to last year's Sharknado, a film every bit as bad as its title suggests. The portmanteau sums up all you need to know about the plot - which, aside from a series of cheap, cheesy, CGI action sequences, is as non-existent as can be - and the attraction that made everybody's inner nine year old squeal with delight. It's the sort of jolly rubbish that comes ready packaged for the ADHD Twitter brigade, a meme-able #LOL fest that people can gently snark along to in real time. For makers SyFy and film studio The Asylum, the numbers made it a hit: pushing revenue for the studio up to $19 million; 2.1 million viewers tuning in; nearly 600,000 tweets during and after its premier alone, all manna for advertisers and TV executives. Everybody wins, right?

Wrong. It's not simply that Sharknado and its sequel are bad films - although they are, by any measure, eye-gougingly, brain-meltingly bad - or that B-movies should automatically be dismissed as trashy and classless; the filmography of Ed Wood, for example, contains some endearingly joyful movies that are impossible to hate. No, what's disconcerting about these films is the way people now luxuriate in just how awful they are, like pigs rolling around in particularly pungent shit. The "so-bad-its-good" mantra - previously applied to film makers that strived to create something special but failed miserably, with hilarious, unintended consequences - has been extended to make sheer awfulness, in all its forms, the main reason to even watch in the first place; "Flying sharks in NYC - what's not to like?" ask commentators, tongue only partially lodged in cheek.

Even worse is the fact that the people behind The Asylum have gone out of their way to make it so bad. Specialising in so-called "mockbusters", Sharknado is just the tip of a particularly large iceberg; Transmorphers, Megashark vs Crocosaurus, and Nazis at the Centre of the Earth are just some of the studio's recent output (sharks seem to be a particular favourite, starring in six of their titles). These films are assembly line cash cows (as is much of Hollywood's output, I know), rush produced - four months from conception to finished product - and built around the type of one note jokes that only seem clever through the fog of late night weed smoke. ("A two headed shark! Giant mutated alligators!") As film critic Doug Benson put it: "Fuck you if you think it's funny...try hard, so I can laugh at you."

Not everyone can be Nolan, obviously, but at least filmmakers used to aspire to something, pouring every ounce of their creative talent - even if that was very little indeed - into what they hoped would be some totemic social document or acclaimed addition to the visual arts. The SyFy approach is not what makes B movies so great; they're far too cynical and knowing for that. Troll 2, Tremors, Miami Connection; their makers had at least some noble goal in mind when they set out, and seeing them fall short of their lofty ambitions is what makes watching these films such an enjoyable and engrossing experience. As soon as you start deliberately filling the screen with bad acting and clichéd in-jokes, they lose all charm and wonder. You or I could sit down and within five minutes bash out some brain dead film "concept" that would be the equal of anything they've produced, a state of affairs that misses the point of film-making entirely.

This, however, seems to no longer matter to the population at large. Unbelievably, Sharknado currently has an 82% rating on Rotten Tomatoes, placing it above Fight Club, The Royal Tenenbaums, and Oscar winner Crash. Even those normally quick to condemn cultural abominations, like best-selling author and Twitter celebrity Kelly Oxford, have been sucked in. A self-styled Queen of the 140-character-put down, Oxford has a cameo in the sequel - spoiler alert, she doesn't survive - and spent most of its release week gleefully tweeting this fact to her 581,000 followers.

But what's really worrying is that this fetishisation of the dreadful is not limited to a few, straight-to-TV absurdities - nowadays it's applied across the cultural spectrum to all manner of tosh. Taylor Swift, 50 Shades of Grey, Dan Brown, manufactured pop, Doctor Who, Pirates of the Caribbean, reality TV; they're all championed in ironic fashion, mundanity being the new "amazing". Dare to criticise these hallowed chattels of awesomeness and you're dismissed as a "hater", "buzzkiller" or, worst of all, a "cultural snob" of the highest order. One's taste, and what that says about one's class, is the new cultural battleground, a fight for the hearts and minds - not to mention cold, hard cash - of content consumers in the 21st Century.

It shouldn't take a genius to realise that you don't have to think you're better than something in order to (rightly) criticise absurdly low levels of quality and ambition, or that even debating the merits of such utter drivel helps drive their spirit-crushing, unstoppable rise to ubiquity. Watching, listening, and posting about any of the above only encourages people to make more of it, hoovering up development budgets, column inches, and cultural capital, pushing those with genuine talent and ideas further to the fringes. Defend it as "harmless fun" or "just a laugh" and when - for it will surely be when, not if - Sharknado 6 sweeps all before it, you'll be personally responsible for at least one of the nails currently being hammered into culture's coffin.