I guess that's an issue if you move states. I'm in the UK, and I know someone who moved 8 hours away to a different part of the UK. Would never have even been considered pre-covid, but the evidence that they could work productively from home was there: they'd been doing it for a year already! They're a manager too, so regular collaboration is a given. It's just all online now.

Keep in mind that 11 US states by themselves are larger than the entirety of the UK; Oregon, for example. I don't know if tax is assessed differently for say Scottish rather than English residents, and 32 US states are larger than England.

This is going to be an issue if you move anywhere within a country with a federal system of government. For EU residents I imagine this also gets tricky for people who decide to WFH from other countries.

Yeah, that was kind of my point. There's plenty of room to move within a US state without running into these issues. FWIW I believe the income tax system is the same across the UK. There might be different local taxes in Scotland, but your employer wouldn't need to concern themselves with those.

No, Scottish income tax is different, so the employer does need to deal with it. (Though I imagine most UK payroll systems have such options.)

Scotland has a different legal system than England. It seems unlikely that wouldn’t have an effect on remote work?

As someone navigating this right now - it's a mess. Business is in a no-income-tax state, I moved to 4% state, and it was deemed easiest to be personally responsible for paying quarterly estimates so the business isn't on the hook for paying business taxes to a state it doesn't do any business in. Some states, however, decided now was a good time to declare a single remote worker in their state means that company has a nexus there, and thus owes all corporate taxes to that state.