Yes. You can use tailwind with sass as well though it's not recommended.

Think of tailwind as a framework for all your styling needs while sass is more a functional language to generate CSS for you.

Partially. You'll lose the system Tailwind gives you, which makes it easier to be consistent.

I handcraft that system myself.

It's like buy Ikea furniture and assembling it vs. having your own woodworking shop to handcraft furniture with precise requirements. These frameworks have made me lazy. I think CSS design is pretty much exactly the same as any craftsmanship job - there is so much pleasure from building it from the ground up. No, I still get the knots in the wood out by using reset.css.

Also, I try to not use class selectors as much as possible. HTML looks sterile and spartan with only a handful of span tags or id tags for very specialized targetted changes.

I can see why people use frameworks - its fast and quick. But you lose personality in the outcome.