So on one hand Ajax is filthy rich nowadays and nothing big to spend it on (a 50m player will not go to the Eredivisie). And Ajax is in danger of getting robbed from all their good players. The crown jewel is already lost after this season (Frenkie).
On the other, Ajax doesn't have a problem with players wanting a transfer when they're ready, even if they don't need the money. New talents are waiting for their chance. New potential signings know Ajax won't be difficult, and might not pick Ajax if they had a different reputation.
So I think it will go like this: Ajax will set a very high price, possibly higher than Frenkie's. If Barca is willing and capable to pay it, he will go there. If Barca can't, it will be more interesting. Then Juve, United, etc. come into play. If he's really longing for Barca and doesn't want to be stuck elsewhere, he could pick up another pay raise and remain patient at Ajax, in the hopes Barca has the funds next year. But I doubt that.