Apple despises user freedom. Their whole thing is "use what we gave you and be happy for it". They would never tolerate letting users do something like run any app of their own choosing.
Sorry, I should've clarified that I was asking about whether you had a source for the claim that this legislation will not allow sideloading. I agree regarding the definition!
I just read the article, which like OP says, talks about third-party app stores and not sideloading. If it's anything like EU regulation, then that'll be that.
It uses the word "sideloading" and doesn't appear to have carveouts allowing Apple to block apps for "security" like the EU legislation does. But at the end of the day it really just depends on what their legislators are going to allow Apple to get away with, and Apple will probably attempt bare-minimum compliance at least initially, like they did in the EU.
