Judging by the games and demos released game engines are scalable, and if the seriesS was "crippling progression" we would not see concessions on the ps5+xsx version of the matrix demo.
Even cross gen games like fh5, FW and gt7 are well received on current gen consoles despite them being cross gen.
I mean if the seriesS is holding back the xsx + ps5, then show me.
But it does not really matter, people will complain if they want too.
You've quoted developer comments a little earlier which disproved your own idea yet you fail to realise it.
4a Games have said similiar and there are more publicly dissenting developers out there.
Slowing progress directly or indirectly and potentially limiting game design doesn't sound great for owners of the bigger consoles.