I suppose on one level this isn’t a shock. For the last year or so a normal raid boss is around for about a month, with occasional special or repeat ones that pop up for a week or so between the month long runs. If we follow that established pattern, should we expect 2-3 months of SB Mewtwo in EX raids followed by whatever comes next? I doubt they would do a full year of SB Mewtwo again.
Also, will SB be opened up to TM, or will the TM pool remain where it is now, with Ice Beam, Flamethrower, Thunderbolt, Psychic, and Focus Blast? I suspect not, and that the only way to get these special moves will be to get them when they are in raids.
Many of the people in one of my raid circles (the one on campus) don’t have any SB Mewtwo, and will likely be frustrated at this, since we don’t have an EX gym on campus (missed on one by a few feet). Most of them are students, only a few have cars, and the time to go to a random raid at a far away EX gym for a small chance at an EX pass isn’t something that fits into a student schedule. But for most of the people without SB Mewtwo, this is a real boon. Of course, Giratina (Origin) is a better ghost attacker, but there’s something about the OG Mewtwo with PC/SB, …
Personally, I have four SB Mewtwo, best is level 40 with 15/12/15 IVs, haven’t bought a second move yet. Not sure how much effort I’ll put into getting another. Caught a shiny yesterday (albeit with awful IVs), so that box is checked, and I have 9 with Psystrike, including the shiny. So on a personal level, Mewtwo in EX raids is so-so news, I suppose. On the other hand, now that the other kinds of Mewtwo are out there, SB Mewtwo makes a great trade piece at normal trade costs - help someone else without SB out, and get something good in return, lucky trade or not (best to save for lucky trades).