I'm sorry, guys. I mentioned that UDIM is more common in game engines and game assets. This is NOT true. My mistake. I just reviewed some information on UDIM, and apparently it is far more commonly used in VFX pipelines which require multiple texture sizes for close-up shots vs. distance shots on the same model. However, it is being adopted more in game engines today as well for the same reasons (especially now with the advent of extremely fast RT-supported GPU AAA games). However, my previous opinion still stands. I think it easier for the end-user to decide if they want UDIM than to provide it in all your assets. However, if you find yourself creating models for VFX where you are generating texture maps for some parts that exceed 8k, then it may be useful to incorporate UDIM instead.
There may come a day where UDIM is the standard for all asset creation, but for right now I don't think it's necessary for every asset. Depends on what market you're designing for, and is it specific enough to warrant UDIM workflow for those assets?