Similar to you argument against Monero, mixing is also putting your coins at risk because exchanges can also freeze your account if the see your coins went through a mixer.
I agree that mixing is also a not 100% perfect solution. And it's not because the horror (stories) of mixing with fraud money (which is rather unlikely, based on statistics), it's as you said, because of certain exchanges' policy, which is also overly inflated (I did sell mixed bitcoin at centralized exchange).
Again, neither solution is perfect. I just wanted to mention one more option you didn't have in your list.
PS. I am quite a fan of Monero and it makes me sad that it doesn't have the success it deserves. I still hope that the world (of crypto) will wake up and stop allow just anybody look into their pockets like it happens now.
The whole idea of my argument is developers will find solutions to problems. I am quite certain there are many developers left who want to fight government’s intervention and proneness to tyranny.
This is a rather complicated thing. As long as Bitcoin has now a great success as it is, doing big steps towards making it privacy oriented may hurt it, possibly even permanently. Bitcoin started getting accepted by the big financial institutions, while Monero gets - now and then - delisted from exchanges. Imho one big component of Bitcoin success is that the agencies have understood that Bitcoin is - in most cases - easy to track.
If you mean that altcoins add more privacy features - that's fine, but won't help much. There's already Monero for proper private coin and its success is rather limited. Litecoin wants to get back into attention - well done - its struggle may be a test ground for Bitcoin as a later move, but don't rely on that too heavily.