I cannot be alone in feeling that titles (within "tech" in particular) are almost completely arbitrary? What constitutes a "senior", "lead", "principal" and "staff" X, respectively, has so much overlap that it really depends on the organisation. I myself have been called all of those things, but have honestly not been able to tell the difference: in some cases, I have had much more responsibility as a "senior backend…
Which is actually an issue in our industry, I think, and it's causing widely different expectations and skills in different companies. A "lead developer" for company A might be considered a medior at best at company B.