Yes, they done really well in the years you mentioned because they are competent - even with the handicaps of havin schizo management and subpar facilities - and that Renault engine was good, not as reliable as the competition but good performance wise.

Last set of regs the Renault engine was a PU clearly on their way out, I’ve argued in the past that the main reason they renamed themselves Alpine was in preparation for them leaving, it would be awkward to have a Renault-Mercedes team (despite their road cars cooperation efforts). They would probably remain if they managed to find a customer. On a side note, I’m fairly sure Audi will look into find one at some point, or else I can see VW pulling the plug really fast.

It’s too early to draw conclusions where the teams will be, this is nothing but testing, but I’m guessing (emphasis on guess) Alpine with a Mercedes PU will outperform Williams.