Eh, not necessarily a problem. That’s how you get innovation, as long as the systems are compatible at a base level.
Two things I can think of, offhand, that California might want/dp to improve the Digital ID landscape are, (1) something to give more discrete control over the information presented (very much in line with other privacy initiatives in CA) - think of having it show up in Apple Wallet as several IDs (all you), that present varying levels of information, and you choose the one to present, so the bouncer at the club doesn’t get your home address, but the TSA/cops get everything. The simplest one might show a large picture of you, and give your name and age and nothing else (and, of course, its existence infers you are a resident of CA). The more detailed one could give full home address, date of birth, drivers license status (expiration date, classifications for motorcycles/semis/etc) / restrictions (requires adult supervision, needs eyeglasses, etc.), and so on. You show the full one to the cops, you show the restrictive one to the bouncer, waiter, checkout clerk, etc.
And (2), they might be setting up the laws to mandate that the Digital IDs are just as valid as the physical IDs, so, say, a liquor store can’t say, “nah, we wanna see a physical drivers license”.