So what is the correct block size for true adoption?

If you start increasing it, you start getting other issues.  Hash rate will go down, due to less profitability.  Decentralization will decrease, due to higher hardware/network requirements to run a node.  

AND you will still eventually need to move to a Layer 2/3 anyway, because onboarding the entire world for small daily transactions on Layer 1 would require massively large block sizes that will certainly centralize the system into a few massive super-nodes.

If we would need to build layers eventually anyway, why not do it now, and not make any tradeoffs that would compromise the base layer?  

Look, I'm seriously concerned about this issue for BTC and I have a lot of sympathy for the things you are saying.  You aren't wrong.  But I also feel like you haven't thought this out completely.  I don't know how to fix this, but I know a block size increase isn't the magic bullet that big-blockers think it is.

https://stacker.news/items/369209/r/Nuttall

Because it doesn't fix anything.

There's no good reason why there should not be an increase in block-size, and the whole competition for block-space might very well hinder Bitcoin from *true* adoption, not just people hoping to sell it higher.

Fabs

Well, you can create your own fork and "fix" Bitcoin. Others have tried before, so why don't you give it a try?