Intertia. TS is way more popular than Coffeescript ever was, so there will be more code to maintain, and the network effect applies here.
> The cutting edge JS ppl are moving away from TS right now, at least some of the ones I follow on twitter seem to be over it.
Who are these people, why are they moving away from it?
> OP might be on to something, not wanting to waste time chasing trend n-1
If you need static typing for JS now, TS is your best bet. You can also wait N years for TC-39 to add it but so far nothing has been proposed.