To the bolded - what does the accountability involve, if it's not all financially motivated?
There's been many a time where officials who are generally percieved as "bad refs" make it into the later rounds as well.
Yes, and all of the things you described are common practices in private corporate environments. All reasonable and understandable in those places of employment.
The difference is that this is the world of professional sports entertainment where their performances (or lack thereof) are there for the world to see, and hold increased expectations to be publicly scrutinized.
Otherwise, why do we hold the general expectations of entitlement to the information regarding the consequences of player and staff actions (including GMs, e.g. Chayka) when officials, whose actions have very real consequences within the industry, get to be exempted from such public scrutiny?
Bonney didn't go so far as to tell us the details and none of us asked. However, just guessing based on patterns I've noticed, it's not entirely unlike players who perform poorly (or well) - it their performance affects their next contract with the league in terms of whether they actually get one or not, and presumably how much they get paid. Though, somewhat unlike players, seniority also has an effect on the latter. The numbers are about 10 years out of date (but you can do the math on pay increases over time presumably), but linesmen would start out with an annual salary of about $70,000 and referees would start out with an annual salary of about $150,000. A veteran linesman who performs well could expect to get up to $150,000 and a veteran referee who performs well could expect up to $230,000. Underperforming linesmen and referees could expect less, if offered a contract at all. There's some more financial motivation for you, in that case.
Personally, I was never going to make the NHL as an official even if I started young enough, though in large part that's because I'm a woman. I'm 38 now, and there has been buzz about the NHL making a run at hiring female officials - though only as referees, not linesmen - but that still has yet to happen. What I could have hoped for had I started younger and continued officiating, is to eventually get higher-paying game assignments, and more of them. If you don't make it to one of the very few leagues that hires officials as full-time employees, you get paid on a per-game basis. For my situation, being from Arizona, there was a big difference between getting only 5-10 games a month at around $25 per game (about what they paid for the average kids game) because you're not a very good official and getting 40-50 games a month at up to $50 per game (what I got paid to be a linesman for high school games, though I had plenty of kids games for less per game mixed in).
Slight digression, but Arizona State University started a women's ACHA program around the time I had to move away from the Phoenix area, and the men's ACHA games paid $200-250 (I imagine the women's games would have paid around the same). Being one of the few female officials in the entire state (I think we had like 5 total), I could have easily cracked into doing those games, then maybe getting noticed by the NCAA. That's probably about where I would have topped out.