how does that difference translate to one stifling imagination while the other does not?
Because one has a far greater capacity to capture the sustained interest/engagement of a large enough portion of the hobby, as well as a more vested interest in keeping them engaged with what the VTT does, i.e. incentivizing monetization via recurrent spending, encouraging user investment in things they can buy, which are likely to be audiovisual things (which has the unintended consequence of pulling attention away from what it doesn't).
I agree that WotC should be capable of producing the fancier VTT, 3D, animations, etc. but I do not think that the level of sophistication is your concern.
It's part of it. I keep trying to say that there are multiple aspects to this, in terms of technology, brand engagement, monetization, etc.
Owning the content or not makes zero difference to me, is your fear that they will tailor content to better fit the VTT?
To be clear, when I'm talking about ownership, I'm talking about WotC's ownership of the game they want people to use the VTT to play. A company like Roll20 doesn't really care what game people play on its platform, but it's self-evident that WotC wants people to play D&D on theirs.
What would that even look like? I’d say a rules-heavy TTRPG with good automation benefits from a VTT, but that does not mean it limits imagination unless you think the existence of the rules themselves already does - and even then 5e is not really rules heavy…
As I've explained many, many times now, the concern is that engaging with the VTT will incentivize engagement with what it does well, which necessarily disincentivizes engagement with what it doesn't. If you use a thing, then generally you use it for its intended purpose, particularly when it can make it harder to use it for something else. The result is that people are encouraged to color within the proverbial lines more, narrowing the scope of the imaginative play which makes TTRPGs different from other kinds of games.
