It's usually the rubber seal that keeps the water out of the bearing that fails first. I think anything over 1,600 rpm in a washing machine is a bit overkill, as it adds a lot to the cost for minimal benefit, and also increases creasing.
Here's the residual moisture vs spin speed from the service manual covering my 7kg Zanussi branded Electrolux. For what it's worth, it's a 1,400rpm model, which actually spins at 1350rpm measured by its own electronics, and has 6306zz and 6305zz bearings, the inner one seized after 10 years, due to water ingress and I'm pretty sure they'd both still be in good order if the seal around the shaft was able to last longer. Mine rarely last more than 10 years, I suspect the limescale from my very hard water speeds failure up. I think the longest lived was a 1980's hotpoint, it had a weep hole between the bearings so I knew about a year+ in advance that the seal was leaking and its bearings would be on the way out.
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Some people buy cheap spin dryers which can spin up to about 3,200 RPM to save money on tumble drying, and turn the spin speed down on the washing machine to try to make the bearing last longer.
As I recall the centripetal force depends on the square of the rpm, so rpm makes a more significant difference than drum diameter.
