No, this is the same migration. This is my point: you weren't actually forced to migrate until now. The migration has been optional up until this announcement, and many people haven't. What your team did 2-3 years ago, the majority of organizations have been putting off. But now they can't anymore.
So they've basically said 'GA is closing unless you want to pay 120k/pa so move to firebase - GA is now Firebase Analytics' to now 'Firebase Analytics is Google Analytics again, but that thing we said you had to do you now have to definitively do?' ?
...and there's been very little movement. We can still create "universal analytics" properties, we still can't do the same stuff in Firebase, and the GA4 "Measurement Protocol" is still in beta.
I think our eventual move is going to be to a non-Google product.
There’s heaps of good ones around now - our shift to amplitude was a good one but I know there are a lot of other really simple and free ones about too
On the website side of things, which is GA's core user-base, Universal Analytics has remained supported up til this announcement.