This 2017 post makes some compelling arguments for switching over to Scryfall.
But it's 4 years (and a change) out of date.
Before we commit to mass-fixing the currentlybroken gatherer links, can we double check that:
a) this is a super-simple no cost batch update; or b) we wouldn't rather switch search engine to Scryfall at the same time
If the mass-fix is a simple low-cost low-risk batch update, there should be no reason to wait. If it's more complicated/costly than we realise then I'd rather wait.