Guild Wars 2

If you assume that you had all the merits needed for guild missions and several million influence, could a guild just mass speed boost all of their upgrades and mission unlocks and unlock everything near instantly?

Yes but it would cost a stupid amount, rushing guild rush by 25% costs 125,000.

you would need alot of merits too, which are fixed, you need to wait 9 weeks of grinding merits to be able to unlock all of them i believe