I worked in baseball for five years.
There's been a huge push for a ratings system or some sort of umpiring accountability for officiating. Or at least some sort of evaluation that goes on. I'm not a robot umpires guy, but i'm pretty progressive in terms of being a huge analytics guy, etc. But i'm fine with human umps. Just not the bad ones.
And there are so many ways where we can tell if they're bad or not. And there are some that are really, really, really exceptional. But like any union, the umpires union isn't into that. Seniority > performance always.
The older umpires experience skill decline like anyone. Most of them just shouldn't be umpiring. Some of them just weren't ever good mlb umps to begin with. Hernandez by every standard has been objectively bad his entire career AND he's a flaming pile of poo as a person. He's not even that popular among the union guys, but the train of thought (again, union mentality) is you do that with him, flood gates, locusts, famine and the world ends.
What's worse is AAA has some guys who are freaking incredible umps, young and motivated. And they get stuck in AAA for years to the point where they quit because those MLB spots don't open up. Those are the guys I feel bad for.
There's a better way and Hernandez literally can't see past his nose anymore (he couldn't ever, really) and shouldn't be an MLB ump. There should never be a situation where you're correcting 5+ calls in one game due to one guy messing everything up constantly. Bad calls happen, that's why there's replay - and even that's not going to solve all the problems. But last night was past inexcusable by any standard, let alone a playoff series between your league's two marquee franchises.