To get to the point, for users forced to use Oyster/Freedom Pass cards (millions), what's the solution likely that TfL will go with? Because AFAICT, they don't seem to have any plans in place to deal with such users who cannot use contactless cards...? (don't get into technical language, I'm talking about how the London system specifically would realistically work for these users.)Nope. The impetus to make a digital version, or digital equivalent like passes on contactless, is the cost of making and distributing physical Oyster cards. TfL says that contactless is cheaper for them than Oyster, I gave the link above. Plus you have environmental mandates from government, somebody just needs to point out that x tons of CO2e are produced by Oyster cards per year.
If TfL is shouldering these costs, then TfL is going to demand a cardless solution. If Cubic's contract has them shouldering the cost, then they will implement a cardless solution.