I am very open to feedback, thank you for sharing your thoughts. As a quick note just as a reminder, I'm on the PM side of things, so I don't have ANY influence on SWE hiring, and things might not work the same way over there. With that caveat:

Last interview in Jan and hiring committee in March is a terrible experience, and I'm sorry you had to deal with that. When I notice a packet where the interviews were more than a month prior to my seeing them in committee, I ask why, because it's a bad experience. The reasons I have seen that happen are:

- The interview feedback was mixed, and the recruiter wants to go line up a hiring manager to write a statement of support to the committee to help make the case, and that can take time.

- The hiring manager who was already attached has to pause hiring, or is in final talks with another candidate, or goes on leave, and something gets dropped for a while

I'm sure there are others, but those are the big ones. BTW, neither of those are acceptable reasons for things to have gone the way they did for you, I'm just sharing how I have seen it happen.

I'm not sure if you team matched before or after your interviews - at least at Google, they mostly used to team match after interviews and hiring committees, and are now pivoting to team matching BEFORE interviews, partially to avoid experiences like you describe. If a hiring manager is interested and engaged and supportive upfront, they can help push and move things along. In addition, if interview feedback is universally positive, they're looking at skipping hiring commmittee entirely, or doing a lighter review in the interest of speed.
In general, I think these are positive changes that hopefully will streamline things, but it's new and we will have to see.

One point I do want to address is that hiring committees, at least at Google, are not rubber stamps or sanity checks before hiring - we are expected to carefully review each interview against the assessment rubrics, read the notes, ask follow up questions of the interviewers as necessary, privately vote, and then jointly come to a consensus on our recommendation.

Of the packets themselves, those are largely negative don't even go to hiring committee, so we only see the ones where there's at least mixed positive and negative feedback or better. I would estimate that perhaps 10% of the packets I see are "hire" or "strong hire" across the board, and those are the ones where it's a quick sanity check to make sure that nothing unusual happened (e.g. one interviewer was the hiring manager and two others were people who report to the hiring manager). Those are easy, it's great, but it's the exception.

Most packets are a mix of positive and negative feedback, because people are people and conversations are hard, and you're trying to remove as much bias as possible, but stuff happens. Maybe the interviewer wanted a particular answer they didn't get, or maybe there was a misunderstanding, or maybe the candidate got flustered. So when someone says "TC did poorly on this dimension", you look at the notes to see if you also see that, you try to interpret whether something else might have been going on, and then you go look in the other interviews to see if maybe signs of that dimension show up there, positive or negative. Positive? Maybe it was a bad discussion, and you can focus on the other positive signals in the other interviews. Negative? Seems like maybe this is a gap in the candidate's skills.

I'm absolutely not trying to defend your experience, because it's indefensible, and I try to raise a stink when I see it happen (which is not that often). But I wanted to add some context about the role of the hiring committee and the work that goes into making those determinations.