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.