I don't think that Mega Latias is as blatantly banworthy as our last three bans, but I do still think that it's an unhealthy presence that should leave for several reasons. I'll start with the most significant one.
A few people have already brought up the correlation between Latias and Mega Latias. I haven't seen much debate on this, but I think that it's a very crucial point to address. These are not two completely different Pokemon and they should not be seen as such. You need Latias in order to have Mega Latias. The moment you see Latias at Team Preview, you must take into consideration that it could very well be either of two forms and that it's not as if one form is significantly superior to the other. You may be able to infer which variant it is if the team carries another Pokemon that obviously needs to be Mega Evolved in order to be viable (such as Sharpedo or Aerodactyl), but I find that this isn't the case more often than it is. You also need to take into consideration that each form comes with its own share of viable/common sets. Essentially, the presence of Mega Latias in the tier simply gives Latias multiple new sets to run. When you look at it this way, the question should no longer be "Is Mega Latias broken/unhealthy?". Instead, it would be something along the lines of "Does Mega Latias make Latias as a whole broken/unhealthy?" In my opinion, the answer to the former question would probably be no, while the answer to the latter is absolutely yes. Fear not, as opposed to banning individual sets that make a Pokemon broken, banning just Mega Latias is not a complex ban.
In all honesty, I didn't find my laddering experience for reqs overwhelming, but I also took note of why I thought that was. Firstly, I think that every single Latias I saw was Mega Latias. Additionally, from the decent amount of games where I was using some form of Z-Move Latias, I noticed that many teams were unprepared despite being fine against common Mega Latias sets. I also tended to only bump into a few variants of Mega Latias, most prominently either Reflect Type or Defog + 2 attacks (usually boltbeam) and Roost. Surprisingly, I only ran into either CM + Stored Power or CM + 2 Attacks a handful of times. I also exclusively ran into bulky variants of Mega Latias. With offensive Mega Latias sets as well as base Latias being rare if not unseen, I wouldn't be surprised if other people found the suspect ladder to be underwhelming as well. However, I don't think the current state of the ladder is a good indicator of whether we should ban Mega Latias or not. If you haven't found the Mega Latias meta overwhelming now, you probably will when people stop focusing on just that specific form of Latias and only several variants of it. I think that Offensive Mega Latias will gain traction eventually and that people will revert back to using base Latias as well. You may be able to prepare for several sets, but you probably won't be able to make a good team that is prepared for all or even most of: Z-Move(multiple variants), Choice Scarf, Choice Specs, Defog (multiple variants), Reflect Type, Stored Power, Calm Mind + 2 Attacks (multiple variants), Offensive Mega Latias (multiple variants). I see that people like to focus on individual sets, but you likely won't find Latias broken unless you look at it as a whole. It also helps to note that Latias is now by far the most versatile Pokemon in the tier and Scizor isn't really comparable.
Just one more point that I wanted to discuss. I think the fact that status is the most solid way to deal with Mega Latias is far more concerning than the anti-ban arguments seem to portray. For one, Toxic is the primary status that Mega Latias fears, as well as paralysis but to a lesser extent. Mega Latias will gladly take a burn, and even being just regularly poisoned isn't the worst thing in the world. This could lead to some pretty ridiculous scenarios, such as never clicking Will-O-Wisp with Rotom-Wash, or never clicking Scald (seriously, why else would you not click this thing?) with whatever other bulky water you're using so that you don't make the opposing Mega Latias immune to its main weakness. Also, carrying heal bell support is not a heavy amount of team support for any team archetype that's not offense. Balance has several good options for this in Sylveon (which is fairly underrated right now), Togekiss, and even Umbreon which seems to be gaining at least a little bit of traction lately. Stall teams of course have these same options as well as Blissey. Heck, a stall team that I was using for the last stretch of reqs even utilized Tsareena for Aromatherapy. Not that I'm trying to say it's a good mon or anything (though it fit the team). Also, as opposed to having to switch into strong attacks, switching into Toxic generally isn't as overwhelming. I simply don't think that Toxic being the main form of counterplay to Mega Latias is a good indicator of it being healthy for the tier. I'll definitely be voting ban when the time comes.