While planning a trip to the US, I found the following:

• Roam like Home is now $12/day, up from $10/day, up from $7/day when I signed up in 2019. The maximum days is now 20, up from 15, up from 10. This means that instead of being charged a max of $70, you could now be charged a max of $240.
• Even a smartwatch counts! If I use my Apple watch when it's away from my phone, I get charged another $12/day, with another $240 maximum. Same goes for my Surface, iPad, etc. Each one is a separate $12 even on the same day.
• Even if I don't do anything on my phone, if I don't turn on airplane mode before I switch to a US tower, I will be charged ... on every goddamn device.

I dearly regret not keeping an AT&T SIM around, because even $12 of this nonsense is more than Rogers deserves. I'll be getting AT&T prepaid as soon as possible, hopefully as an E-SIM. Once upon a time, AT&T was my main provider because they had free roaming in Canada. I'm going to be investigating other providers and their roaming costs, but honestly I know this game by now; once one gets more expensive, the others follow.

Update: I went to the AT&T store. I now have a 15GB plan for $40 which includes roaming to Canada (and maybe Mexico too.) There's also a $30 5GB plan that doesn't have roaming, and a couple of unlimited options. In my experience, there's a six-month cap on how long you can roam outside the US, but it's not enforced. This was super easy to set up and everyone who travels to the US often should get one.