For Mac, I'm not super in touch, but I get the impression Apple is all in on Swift UI, and their developer support model is clear: use old tech at your peril, it may not be supported in the next version. So I would use Swift UI.
For Windows, I think it goes the other way. Microsoft is always coming around with a new UI model that's half-ass and will be dead next year. Use the old ways: MFC will never die.
For Windows, I think it goes the other way. Microsoft is always coming around with a new UI model that's half-ass and will be dead next year. Use the old ways: MFC will never die.