I think the issue plaguing a lot of these keynotes is just that the amount of time/enthusiasm of the keynote doesn't match the actual excitement/novelty of what's being introduced anymore. For example, at the last keynote, the one thing I got super excited about was that upcoming MacOS feature that lets you control Macs and iPads with the same mouse and keyboard! Of course, it'll be at least 3 years before all my hardware is compatible, but still...
I don't think things are more dumbed down than in the old days - remember when Apple launched the iPod? - 1,000 songs in your pocket, copying a CD in 6 seconds - but I do think the problem is the enthusiasm seems more fake and scripted, with a lot of Apple execs clearly reading off cue cards. I think Steve Jobs truly felt the enthusiasm - it was the same enthusiasm he had when he created the item in the first place. And if you're gonna fill up time by having lots of people come on stage and demo what they did, it really should be something impressive.
Interestingly, I think the pure excitement of the M1 transition didn't really hit during the keynote, because the benefits didn't seem real until everyone started showing real world benchmarks of just how amazing the M1 was. The keynote seemed kinda low key in that regard, giving off mixed feelings because no one really knew.