Your points are valid, but that doesn’t mean we should do nothing. Enforcing federation and using copyleft licensing are both strong defenses against centralization and network dominance by a well funded third party.
As far as GPL goes, from what I’ve seen, big tech companies tend to take it pretty seriously. There is no reason we shouldn’t be using that, and other license protections if we have the option.
As for natural centralization over time, I think that is a far less urgent problem than the current risks we are facing, those being major network fragmentation due to the use of defederation, and the risk of centralization around a proprietary platform and/or instance.
Removal of defederation and strong copyleft licensing seem to be natural first steps in combatting that risk.
LineageOS for microg: degoogled android. DuckDuckGo: search. Firefox: web browser. Ublock origin: ad blocker. Proton: email. OsmAnd+: maps.
Only google product I still use is youtube, but I have made some efforts here:
On desktop pc I use firefox with sponserblock and ublock origin to hide ads and automatically skip sponsered content. I also have an addon called unhook, which hides recommendations, ‘people also watched’ etc.
I also use and recommend Odysee as a youtube alternative.
On my TV I use SmartTubeNext, on my phone I use revanced.
I host my own music server with navidrome (and my own video media server with Jellyfin). But when I dont have access to that, I also use ViMusic as a youtube music replacement for (degoogled) android.
Can absolutely recommend any and all of the tools I listed.