CodeWeavers is one of the few companies that I believe really do intend to keep their word - and have the means to do it.
The company has been shipping CrossOver Mac for almost 20 years now - basically since Macs transitioned from PPC to x86. They've rejiggered their software lineup a couple of times, essentially consolidating a few different products (Games, Office, Standard) into a single SKU, but they've always provided a continuity of features and an upgrade path. Put another way, they've been offering the same continually-updated CrossOver product for over two decades now.
Which, since it's essentially the commercial release of Wine, that makes sense. Their whole business model is constantly developing improvements to Wine, and then bundling that up into a commercial-grade software package that comes with official support. So their business model is stable (so long as Windows remains important), as well as the need to continue updating the software.
Given how intertwined CodeWeavers is with Wine, it would be a disaster if they did renege on lifetime updates for anyone who has paid for them. The corollary to that being that if it were to happen, then something very bad must have already happened to the broader Wine ecosystem, as this is how they primarilly fund the whole project.