Episode 2 today. Got someone with a little more brains on the phone. We deleted the 2018 apps, even though the 2019 and 2018 versions all ran on my laptop. Briefly, the 2019 versions ran on my Mac Pro which, by the way, they do with no problem when I use my other Adobe ID, so it's not technical on my end. He closed the case and hung up.
I then went to open Bridge, and the same thing happened: "You have exceeded activations." Another 90 minutes of my life. At this point, I'm inclined to live with the 2018 versions on my Mac Pro and the 2019 ones on the MacBook Pro.
They are just so useless at even trying to comprehend what I'm telling them, let alone finding a way to fix it. I may call them again, as I'm p*ssed at paying for something and not being able to use it, but I don't have much hope. He wanted to screen-share, so I let him, but he didn't do anything I hadn't already done. He kept trying to tell me how the activations are all done "dynamically from the server now," but he sounded like he was making it up as he went along. I rarely need to call tech support with Adobe, and it's always with activation issues. It's draining, I have to say. Maybe I'll try again tomorrow.
Episode 3: Today it worked. I did nothing, which is always a bit upsetting, when it "fixes itself." I always like to know what changed. I called and spoke with a tech from Adobe, who was patient while we walked through it. When I was done, he said "between us, we have had a lot of problems with this sort of thing - activations - since the latest update. Trust me, it will all be fixed soon." For what it's worth, as they say.
Figured I should report back that it seems to be working for the moment.