>There is no physical limitation that prevents us from leaving Sol system.
That's part wishful thinking, part hand-waving. There are tons of practical limitations that prevents us from leaving the solar system based on the nature of space and physical laws.
At best, we could get some "generational ships" out going to nowhere knows where exactly (it's not like we have some habitable planet to even aim to in mind, and the various "atmosphere-making" schemes are pie in the sky and require tens or hundreds of years, plus tons of resources in that "generational ship"), but even that is less likely than regression or extinction here...
That's part wishful thinking, part hand-waving. There are tons of practical limitations that prevents us from leaving the solar system based on the nature of space and physical laws.
At best, we could get some "generational ships" out going to nowhere knows where exactly (it's not like we have some habitable planet to even aim to in mind, and the various "atmosphere-making" schemes are pie in the sky and require tens or hundreds of years, plus tons of resources in that "generational ship"), but even that is less likely than regression or extinction here...