Finlandization started very much before the WW2, as major power were making compromises with regional hegemons, acceding to their claims on their neighbours "as something natural"
It's big power saying "let them have it" basically, and to disastrous results every time.
Yes that happened, but that's not called Finlandization. I know this is pedantry now but the term is pretty specific and not applicable to countries of roughly equal power.
Finlandization means strong country affecting a small neighbour, not applicable to pre-WW2 appeasement policies.