I'm not too familiar with the relationship between developers and publishers, so maybe this doesn't matter, but Disney is the publisher. Tron 2.0 was made by Monolith which is still around today. Tron Evolution was made by Propaganda Games which shut down in 2011.
That certainly can affect how easy it would be for them to update it, but Disney should have the source code, and removing DRM should trivial if they have the source.
https://www.rockpapershotgun.com/2017/07/01/cor-tron-2-0-jus...