It's pretty hard to say exactly what Apple is up to. It seems to me that their huge budget will easily allow them to develop and invest in their new cryptocurrency. I am sure this will have a certain benefit for them. Cryptocurrency is becoming more popular every day, and there are a large number of services that help to
make money in crypto, so Apple's initiative makes sense. Investing in bitcoin may also have benefits for them, but I would not take such a risk because it is a rather unstable currency that depends on a large number of unpredictable factors. I'm sure they know what they're doing.