We've been trying to be more aggressive on AS's on that and similar subjects, namely upgrading projects that are nearing completion when there's the most amount of content to get corrupted in the upgrade...
It's a double edged sword. We do a lot of remodels/reno's of existing spaces where old models (or god forbid CAD drawings) are available, and they do not want to recreate them. So in the client's mind, they are saving money by reusing content they already have, which ends up being a detriment in the end in terms of functionality.
I would love for us to always start on the newest version available. Given the project lifecycle of larger projects, we want to stay on relevant software versions when deliver the model to the client and not have to upgrade at the end like we have been. That said, we have lots of legacy work in 2020 and 2021 still that we need to maintain content for. Being a BIM Management team of 1, I do not have the time to do work twice in various versions, let alone all of what we have available.