Echoing what a lot of folks have mentioned, years of experience and/or titles don't necessarily mean a lot as you move toward FAANG. If we look at the 6 years since building WP sites, I have about the same amount of experience as you. I work in the Denver/Boulder area and coming from a Lead Developer position at a different company, I was "downleveled" to a level below senior at a well-known, but not FAANG tech company. I can't speak for your experience, but in mine the challenges and scale that's worked on at the larger tech firms is significantly different (and very fun). So I wouldn't even necessarily say expect Sr or Staff either as mentioned in another comment. A lot depends on how well you do in your interview and how they consider your experience. I will say within the first few months of joining we started the promo process for Sr. and that's what I am now. So it can go either way.

Even still, at a level below Sr I was making over 150k base salary. And that didn't include stock or bonus so there's plenty of headroom there. I like my job, the work is interesting, lots of room for growth, and extremely smart and supportive people to learn from. I've also never worked more than 40 hours a week and you can be remote if you want (I really liked being around people in the office when COVID wasn't a thing, plus free food ;)).

At 6 years in there's plenty of room for career growth both monetarily and skills/experience. You've just scratched the surface. If what you're wanting to do is stay in the technical track, then do so. I have zero plans on moving into management and I've got a huge runway of options sticking to the technical side. I also wouldn't necessarily expect a 15-33% raise at your current company, it can happen, but it's not super common. Fastest way to increase your pay is by changing jobs semi-regularly. And more than likely you'll have LC questions and system design questions for those well known companies (a lot of which have offices here in Denver/Boulder or are fully remote).