Did you forget that a global pandemic happened like 9 months before these consoles released?
If it weren't for backwards compatibility, the available software this gen would still be just as sparse and would almost certainly drive down the adoption of the new generation significantly. A PS5 is a really tough sell to most people if the only thing it can play is Miles Morales, Godfall, and Demon's Souls and those were $70 games. The fact that it can play your existing PS4 library is a pretty good stopgap to the trickle of available games. Most companies have adapted to the conditions and are more or less back on track, but I'd say most places were operating at 50% output (or less) for the majority of 2020.