Do you think bike frame size is less important these days?

Well.. I did.
My cyclefit barely changed my position from what I'd developed myself.
BUT! I did lots of reading, lots of testing, lots of kilometres, lots of altering, more tweaking, blah blah. People joining here tend to be "fix me up NOW.. fix this NOW.. want want want.." they don't have 10 years to tweak, measure, read, ride, read, tweak, etc. so if they're straight into "why do I hurt" they're hardly going to bother reading a bunch of bike fit theories..

I've generally suggested a fitting if you can afford it and DIY if you cannot.
Get a rule of thumb setup and start modifying variables one at a time noting the effects. Continue.

It is exactly what I do. Takes me about a few months to get a bike set up exactly the way I like it. Just changing saddle position, stem height until it is perfectly comfortable.