I still think that it is important to standarize a canonical Linux core

If you're not aware, Ubuntu Touch is no longer operated or developed by Canonical, they abandoned the project in 2017. UT was then picked up by UBPorts, a community effort to keep alive what Canonical left behind.

Personally, I don't have a very high opinion of Canonical due to their use of CLAs, which also appear to be present in some fashion with UT and UBPorts as well:

I agree that some standardization would likely be beneficial in some areas (such as focusing on a single Phone UI and polishing it up). PostmarketOS is making the most progress on getting real Linux on mobile, so if I had to pick one project to support monetarily, and one that could become mainstream, or partner with a manufacturer like GrapheneOS did with Motorola, I think that would be the project to back, IMHO.