Sometimes it's more a question of software. On older phones badly made sites like the new reddit for example were unuseable in all browsers - until the new Firefox came along.

But sure. Repairability is one thing, it just means that devices can continue the things they were made for. For new workloads they would need upgradeability, which is a completely different beast.

I don't think having repairability will slow things at all. It will simply prune some behaviors corporations engage in that destroy the planet, like glueing in batteries. Stopping such practices will not even make new devices more expensive - we have old designs that did it right. Falling back to them and innovating there could even save money.