I'd leave out the last sentence, it doesn't add anything and just makes the threat to quit more in your face thus confrontational.
Also instead of finishing with "so let me know if that's an option." I'd go more like "so let me know what options we can explore to make this happen." The first one is a take it or leave it, the second says you're flexible on details as long as you get to be remote.
The point is that you communicate that you are very interested in staying, love the team and willing to work with management to find any reasonable solution to make this work. If you make it an ultimatum the more likely response is "Sad to see you go, ok bye."
As much as I think this is true, somehow experience tells me the other way around: valuable employees leaving company X doesn't make company X sweat. Company X just hires more... and there is always someone who can be hired. A couple of months later, everything is alright again and once realized that that valuable employee was just another cog in the machine.
The truly good employers are a rarity.
They don't, especially those who know they can find someone who's eager to jump in and work for less pay.
Really? I thought the market was saturated. I've read many horror stories of people sending hundreds of applications out that lead to a few interviews that lead to zero offers.
If you're already in place and have proven that you're good at what you do, this is the way to go.
"I wanted to let you know that I'll be staying remote from here on out. This last year has been a huge improvement in quality of life for me, and honestly I couldn't imagine working out of an office again. I'd love to stay with you guys (this is a great team), so let me know if that's an option. If not, I'm sure I can wind down my projects by next month."
Good developers are hard to find, and the market right now is on fire, so you're a lot more valuable to them then they are to you.
Even back when that was less the case than today, this was my standard method of negotiating things like long leaves of absence and shortened work weeks. I've written about it previously:
https://www.expatsoftware.com/articles/2007/02/two-weeks-vac...