The difference between Twitter now and Twitter a decade ago isn't in the quantity of vapid interactions; it's the proportion of that to anything else. The slide started a long, long time ago and at some point effectively no one was trying to stop it anymore. I'm sure there are still corners where useful information gets passed on in a timely manner, but like the citizens of so many venues before it those corners have been diminished and isolated to an extent that it no longer feels worthwhile for those not already entrenched in them to bother seeking them out