Passion doesn't equal competence. It doesn't matter if they're passionate about doing interviews, sometimes that even makes it worse because they think they are raising the "hiring bar" but instead doing a really bad job at interviewing. The disinterested engineer doing an interview is less harmful than this type of passionate engineer interviewing.

The current broken system started with Google. They had a hiring problem, too many candidates to interview. So what did they do? Apply principles used for scaling computer systems. Treat each employee engineer as a generic interviewer who can give a generic algorithm question. Scale across all engineering teams to handle the candidate load. That's the Google way, apply algorithmic scaling to everything. It works except when the fundamental problem is a human issue like hiring and customer service. It's bad system but they get so many candidates it doesn't matter. And the company is successful, success hides all failures.

So other engineers in much smaller companies get asked to interview their future teammates. Sounds great in theory. But passionate or not, they have no idea how to do it. So they just cargo cult the big tech companies. Completely clueless copying of a system that was created for a problem they don't have (massive number of candidates).

Only the manager and lead engineer should be involved. They need to take back control and leave the juniors out of it.