You get access to the source code you use. If you pay for an enterprise license, you can access the enterprise source code too, but it’s indeed a proprietary license, you can’t really sell modifications.
I do wish it was fully free & open source (because that wouldn’t affect me, I’m not on their payroll, I just work with the software), but I still prefer the current model over Dynamics 365 or SAP (though I believe Microsoft open sourced some or all of their Dynamics 365 Business Central code too? I haven’t really kept up).
If Odoo ever decides to close their open source business and only offer it with a closed source, you bet your ass there are going to be dozens of forks of the latest open source version. I’m fairly sure my own employer would do the same, our CTO is an open source evangelist. Would probably RiiR the core even.
Not sure why you think the FTC would be the best body to talk to here. Odoo is not an American company, but rather a Belgian one.