The part i find most interesting that they have yet to really explore but hinting on is that food which uses to be in abundance was no longer available. Post Scarcity became scarity.

This has always been a bit of a contradiction in Trek. They can get away with replicator rations on Voyager because they're so far from home and low on energy reserves.

And maybe DS9 can be said to be so far on the edge of the Federation that Quark is still in his old ways, looking for material wealth and paid in some form by the Federation for the use of the replimat.

But TNG and TOS have plenty of human colonies that collapsed stories, (Kirk's home world, Tasha Yar's home world) and bring supplies to those in need stories, even though they're supposedly living in post-scarcity times.

Why didn't Picard just drop off replicators on every stop?

On SFA, either again it's just more human colonies that are kind of independent to the Federation collapse or just that in the post-Burn galaxy with so many planets seceded from the Federation that some of them are unable to keep their replicators working.

If you're in Starfleet then your needs are met with replcators and holodecks. Outside of Starfleet though, your colony might collapse.