Yes they need to. Why? because in order to make money you need actual customers, customers they are slowly losing.
So they indeed "need to change".
If you were to just fixate myopically on Mac as though it were its own standalone company, this would be a bad thing. But in the greater scheme of things, the extra resources funnelled into their other projects such as wearables, health, AR, iOS and content, does seem to be paying off.
The way I see it, the loss of Mac users seems commensurate with an increase in revenue for their other products, especially on the iOS and wearables side. Especially when it becomes increasingly clear that its products like the iPad. wearables, AR and self-driving tech are the future, not the Mac.
As someone who is more deeply invested in the iOS side of Apple than their Mac branch, it’s a pretty fair trade off for me.