You aren't taxed more on larger, more expensive vehicles because the powers that be (or the poster you were responding to) think you're a privileged asshole. You're taxed more because heavier vehicles cause more road wear, and because Washington has no income tax (which are typically progressive in nature), so the rest of their tax system needs to lean more progressive to make up for that. Thus, more expensive vehicles get taxed more.

Did you benefit from paying no state income taxes for decades? Well, now you're paying a little back into the system. I'd think you'd be happy to do that, after having paid no state income taxes for so long. I'd also think you were well aware of the registration taxes when you purchased the vehicle? If so, given these two facts, why are you complaining about it?

You can still be an asshole if you want of course, but being an asshole has nothing to do with your registration taxes.

It's just part of the cost of ownership. Not classy to balk about a few hundred bucks more to register your car when you've paid tens of thousands for it, and are also paying more to insure it, and to maintain it, and in depreciation. Presumably you anticipated all that in the purchase as part of the TCO. Not to mention, the tradition of wealthier persons contributing more to society stretches back in Western civ to the Roman period at least. Better IMO to take some pride in your attainment of some small aspect of patrician status rather than resentment at the responsibilities that come with it.

Nobody called you an asshole, that's you projecting what you assume people think of you. They suggested that your being owning a luxury vehicle means you can afford and should contribute slightly more to society than somebody who doesn't, which is a lot more reasonable than calling you an asshole who needs to be punished.

There’s a big gulf between “not a shit box” and “new expensive luxury SUV” and it’s pretty reasonable to tax more expensive vehicles proportionally.

One thing to look into. If you're married, give the vehicle to your spouse, and note the amount of the gift in a notarized letter. That then becomes the value of the vehicle for tax purposes. We live in a state that essentially has an import tax on vehicles. It's unconstitutional, but you'd have to take that to court and that would take years. We did this with our vehicles when we moved to the state. The person at the vehicle registration place was unhappy, but they had to accept it - an extra benefit.

You're not an asshole to drive around a ride you've earned.

Statists will always find some rationale for taxing more that sounds perfectly reasonable and good, when its obvious the motivation is envy.