Isn't it the other way round? When rents are higher, how well maintained the house is matters less to tenants compared to the location and rent. But when rents are low, they have more freedom to choose a well maintained house.

If you're talking about long-term maintenance so that skipping it is just deferring costs to greater costs in the future, then why would a landlord do that unless they expect to demolish the house before ever fixing it up?