"No user serviceable parts inside"
Or, in simple English, repair requires skill, training, knowledge, some combination of the three, beyond that a regular and common user would possess.
It also works, in the real world, to identify some product that can not, in fact, be repaired at the component level, either due to physical reality (epoxy potted components come to mind) or the manufacturer's inability to source the required components (third-part complex parts, I could offer examples which should be obvious to anyone able to make an argument from knowledge).
Sometimes this is more a statement of reality than an attempt at obfuscation. 'cause some stuff cannot be 'fixed', and the average user would not even understand why.
Disclaimer - I fully support Right to Repair. I also acknowledge the reality that some stuff is really difficult. And in the example from TFA, We are generally talking about equipment that is not so much 'repaired' as either replaced at the subassembly level, or more likely, in the example, problem-solved in software. You want the right to repair your router's software? Or just access to it after the explicit agreement or arbitrary agreement with the manufacturer says no? As in, you paid for support during the warranty period, but after that expired, the manufacturer soon abandoned software support...? Read the EULA. Ask the State to force them to do whatever the State decided to do. Watch innovation die.