The Burn stagnated progress and reverted tech to perhaps hundreds of years in the past?
People keep mentioning this, but I just don't see it.
The UFP was reduced from 350 member worlds at its peak to just 38.
That's 38 member planets that had their technology, databases and resources INTACT.
This wouldn't have caused stagnation. It would have slowed things down yes, but if anything, SF and UFP would have been using adaptive algorithms for R&D. The HQ itself had over 12 ships stationed in the cloaking shield/field... they could have all been networked together and instructed the computers to keep researching new science and technology (those are more than supercomputers for crying out loud with FTL processing capabilities).
Computers like that can do research in a fraction of the time (a day or a few) that would take humans many trillions (or quadrillions and quintillions?) of times longer to do... that's just the HQ... not counting the remaining planets.
Stagantion would have occurred if every single trace of UFP database was somehow erased... and that's virtually impossible to do without completely eradicating every single piece of UFP database in existence (which is spread across a good chunk of the galaxy - aka, each member planet, every ship, every outpost would have the UFP database at its disposal) and no UFP ships were left in existence (let alone the HQ).
And they have programmable matter to boot (though to be fair, transporters and replicators can do the same).
We saw that UFP databases survived the Burn just fine. So, stagnation would not have happened... at least nothing like you suggest.
At the very least, what we saw that UFP (and most species) were using ships and technology that existed just before the Burn happened.
And subspace effects of technology have apparently been discarded by writers completely... suggesting that UFP technology reverted to PRE-24th century status and was BARELY more advanced than the 23rd century.
Here's what I say to that: 'utter nonsense.' :-)