That being said, I don't think Chevron deference has a part to play when it comes to Net Neutrality flip flopping all the time - these are not ambiguous regulations. In that sense I don't agree with the person you're replying to - Loper Bright won't help here. Now, if you want to say that the FCC doesn't have the authority to issue this rule, that's something that was always reviewable by the courts.
The concept that would actually attempt to strip power from agencies is the nondelegation doctrine. While I suspect that has support among a few justices, it would be a very radical change and there is no case on the horizon that I'm aware of that would be a vehicle to implement it.
If Loper Bright had been decided ten years ago we would already know today whether the FCC possessed this authority or not and it would be settled. Instead, we are about to embark on another round of litigation because the FCC just unsettled expectations again.
Case 1: agencies reinterpret the law ever four years in each new administration until the end of time.
Case 2: we figure out what the law means once and apply it going forward until Congress changes it again.
Case 2: Waiting until every single individual aspect of every single law is litigated means for years to decades the actual meaning is ambiguous until each court case finishes.