If the phone number requirement for Overwatch 2 wasn't controversial enough and is a feature that won't go away for new players of the Overwatch series, even the upcoming COD MW2 will borrow that feature. That's Activision Blizzard for you which can mean game franchises coming from both sides. The problems Activision Blizzard mentioned like bots, cheaters and other types of gaming misbehaviors still exist to this day but to make use of phone number to tackle such problems isn't going to help a lot in my opinion as there are concerns of the solution's downside like someone using someone else's phone number to do such malicious activities for instance. So, if you see someone doing such malicious stuffs in the game online, you should report that person. Of course, it's not an easy feat from that point on as once that person's account is terminated for their disruptive behavior, they can come up with another account to circumvent the account termination and continue such nefarious acts using it.
It's like Activision Blizzard downplayed the backlash Overwatch 2 caused and they're trying to extend it further with other games like COD MW2. You may wonder if they're out of their minds enough to cause another gaming controversy in a row or something after a series of controversies surrounding Diablo Immortal occurred. It's worse than we thought but again, people were right to be disgruntled and vocal over such controversies like this. And to anyone claiming that people were "entitled" for feeling displeased, disgusted or whatever over the Diablo Immortal gaming controversies, it'll be best to reflect on this mistake.