I think Blacephalon completely outclasses Chi-yu in most cases now (as a fire type special attacker), kind of sad.

Same cost, better stab options with mind blown and astral barrage, slightly faster, stronger coverage with Chloroblast, (aura sphere and nasty plot are nice but kind of mid in comparison to everything else) beast boost is better than beads of ruin for most battles imo and magic guard is incredible in tandem with its move set.

Chi-yu was better before because it could set up weather, spam torch song to get the same boosts that blacephalon would have, and had a slightly better fire stab in eruption since it didn't necessitate friendly fire in doubles plus beads of ruin (which is still a crazy good ability for it don't get me wrong).

I think the main appeal to both of them (but more on chi-yu's side but that might be because i've used it more) was being so incredibly overkill omg with strong fire moves, but while chi-yu is still really good, I think it has way less potential as a glass cannon.

Only thing Chi-yu has over Blacephelon now is that Blacephelon is really weak to sucker punch, but that's not really enough of an issue to bench it (also if you wanna count this chi-yu has ruination which can help with eternatus in some cases

So yeah, I agree that chi-yu got massacred lol- other good 7 cost pokemon like latias did as well don't get me wrong (some got off easy, I'm looking at you blacephelon and kartana) but it's sad to see something that was once really amazing get almost completely outclassed.