It's hard to empathize when they just made her a dumb brute who drinks the bog dry and smashes the shit out of everything.
I just don't like almost everything they did with Meteora, honestly. If she was still visually old or not like 30 feet tall maybe the same stuff could've been easier to take, but I don't think the transition into a huge monster helped with a plotline I didn't think was that great to being with.
Toffee pretty much stayed the same character type from beginning to end and it was a character I liked in the first place. They had some fun with him in a giant corrupted goo state and that was surprising and a nice change of pace, but it still felt like the same guy. And I get they were going for her breaking down across the season and thus becoming different; it just didn't feel like it was done too well and as a result it just kinda felt like a stupid joke that went on for far too long because they never quite felt like they were pulling it off seriously. The deepened voice didn't help either; they actually managed to achieve some genuine emotion with the VA's performance in Monster Bash when she saw the nursery, which doesn't translate at all to a generic deepened monster voice when we're supposed to care.
Eclipsa was cool in those final scenes but her daughter was and is shit, and it's a shame she's just gonna have to keep being Meteora's mommy now.
okay yeah I wrote too much, the finale was fine but I just sorta have problems with the fundamental concept, while Battle for Mewni worked in almost all areas for me by comparison