The real problem is that even if you meet the criteria listed here, the criteria or examples at other companies will be wildly different.
Six levels from E1 - E6, and objective level details for each of 27 competencies?
What do you mean that "seniors who don't fit"? What do you mean "mids that do"?
What criteria are "wildly different"? Granted, a hiring firm is unlikely to have rationalized the evaluation this well. But it seems unlikely they're looking for something that isn't at least represented here.
Are they? They seem like a manager can justify someone being at that level or not. There's certainly nothing in there about how consistently one must meet each of these. I guess seniors never need any guidance or help from a teammate...
I sort of hate that we have to define it so formally, and it would be nice to think "she's a good dev" and that instinct is it. But in reality a benchmark is needed to be fair and prevent bias.
In addition to be a good engineer you need to code, and coding tests are a way to find out. Ideal ones would be open ended, plenty of time, and with the interviewer "searching for success" to try to counter interview nerves. "Oh yeah I made that mistake I should have done XYZ" is as good as getting it right first time.
In an ideal world there would be some standard basic coding tests to avoid fizzbuzzing everyone. Sort of like AWS or Azure certifications, but for actual coding, that are respected, as a base level. Do them once every 2-3 years say and that is your passport past some useless interview stages. But I digress!
Concept: https://circleci.com/blog/why-we-re-designed-our-engineering...
Matrix: https://docs.google.com/spreadsheets/d/131XZCEb8LoXqy79WWrhC...
Evaluate yourself critically and honestly within every single row. Learn to convey (market/sell) yourself to an interviewer on those dimensions. Be truthful, people can tell.
In the event these interviewers are actually picking up on something, it may be that the "senior" for them is along a dimension they consider more important than a dimension you think matters.
For good measure, begin to work deliberately on those rows where you aren't as far along as you'd like.