It is a valid opinion, and the events described there took place, I just - personally - don't believe the outcomes were caused by the events described, they feel more like coincidences to me. Although Google dropped XMPP at least partially for the same reasons it died - trouble with architecture that made it problematic mobile.
And the comparison is not fair. XMPP was meant to be extended, so complaining about the second "E" in "EEE" is IMHO questionable. Google left a bunch of useful XEPs and even a Free Software codebase (libjingle) that others still use to the day, and I don't see anything wrong with this (and I'm surely no fond of Google, but that's not something I'd bash them for). This is feels very different from what may possibly happen in the whole Meta/Threads/Fediverse/ActivityPub situation - I mean, it's not likely Meta starts contributing to Mastodon project or something. In my understanding, EEE is more applicable to Microsoft and IE (where it surely happened, and a lot) than to Google and XMPP.
IMHO the article is a good read to at the very least be familiar with the events and understand the argument - but personally I find myself disagreeing with the presented arguments, thinking it's quite a stretch. Of course, that's my own, purely subjective opinion.