I think I agree with you on the big lines. Although I'm guessing large population migration will be more due to rising water (most humans live along some cost line). And if millions of people have to move, there will be wars with or without fascit goverments. With this scenario, the 10 year time frame seems pessimistic, I think 2050 is more likely.
Either way, the earth system will regulate, it would be nice if civilisation managed to survive the transition. I'm pretty sure there will still be humans around, happy humans I'm not so sure.
Agriculture will certainly collapse in many places long before sea level rise is noticeable.
We see reduced rainfall in many areas already, enough to have materially affected crop yields and triggered political instability, generating refugees. (Increased rainfall in other places doesn't help.) Insect populations are collapsing already. I don't think we know how low such populations may go before loss of pollination affects crop yields.
The only good news is that renewable power cost is still in free fall. It is not clear if it can be built out fast enough to cut CO2 output. Desalination will fill in for rainfall in some places, rescuing yields, although probably not in the places that will produce refugees.
It's important to remember that cutting CO2 output is simply not enough. We need to displace all fossil combustion for energy with renewables and also generate enough power to sequester the CO2 we've already released by burning fossil fuels. The magnitude of the problem cannot be overstated.
Either way, the earth system will regulate, it would be nice if civilisation managed to survive the transition. I'm pretty sure there will still be humans around, happy humans I'm not so sure.