Problem B may not be completely unavoidable but it also isn't a valid excuse for deliberately anti-repair design choices. Some things are indeed tradeoffs in terma s of repairabilty vs. features or costs, but some design decisions have little to no effect on features / cost but a large effect on repairability or durabilty.

Now, you can't always legally separate which tradeoffs are which, but I do think there is real value to finding ways to incentivize companies that make durable, repairable products. Those products produce a lot of value for society but manufactures can have a hard time recouping much of that value in the sale price, leading to bad incentives.