I have been looking at this for a while too. It certainly doesn't affect me because I don't make anything near the 200k required. It does affect just about every single one of my WA clients and they talk about it.

What I took away from their statements:

If I ever do get close (and it would likely be through the sale of my biz), then I would make a plan to ensure my earnings fall well below the margin per year where the buyer pays me over a longer period or, more likely, I'd just move my business out of this state and establish a residency elsewhere to serve the purpose.

Ultimately, rich people are rich because they're good at maneuvering around tax laws like this one. There are plenty of ways to make your "adjusted gross income" look like it's a lot less due to non-monetary compensations, divided residency, shelters, foreign tax credits, etc.

In the end, I'm quite undecided about how I'll vote on this one. I agree with all your points about letting a 20k-earner spend more on their own well being and less on taxes through that spending, but I'm also wary of a tax plan that endangers my business (through my clients) or the eventual income that I hope to make (a good problem to have).

It'll be interesting to see how this one plays out.