While the right of access is not granted by AGPL - it is not reasonable to run a public service with an AGPL client and say you shouldn't be connecting to it.
They are doing a lot of work to create implied consent under CFAA.
If you want to control access you must do something to control access - it must reach a threshold, it cannot just be a public user agent string.
Unfortunately, the CFAA doesn't necessarily require that authorization is implemented through technical means, and it definitely doesn't require any authorization to be technically robust.
This is a direct quote from the Affero GPL:
> When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures.
The thing Bambu is doing is very much against the spirit of the AGPL, which is the license they chose for the Bambu printer software. And the AGPL has such broadly written language it's hard to believe what they are doing complies with the letter.
Elsewhere, the GNU explains why this is important[1]:
> With proprietary software, the program controls the users, and some other entity (the developer or “owner”) controls the program. So the proprietary program gives its developer power over its users. That is unjust in itself; moreover, it tempts the developer to mistreat the users in other ways.
> [...]
> Freedom means having control over your own life. If you use a program to carry out activities in your life, your freedom depends on your having control over the program. You deserve to have control over the programs you use, and all the more so when you use them for something important in your life.
Telling your users they can't run modified versions of your open source client goes against this principle.
Again, I'm not necessarily saying Bambu isn't within their legal rights to do this, I'm just saying it's a jerk move.
[1]: https://www.gnu.org/philosophy/free-software-even-more-impor...