With SoH decreasing the internal resistance increases and the battery inherently becomes a fire hazard. At some point the energy required for cooling will not be justifiable and the battery will have to be decommissioned.
As internal resistance rises, you just need to charge slower...
A battery that normally takes an hour to charge can charge 10x slower and take 10 hours to charge, and still be providing some useful value. (nearly everywhere will have a day/night power price discrepancy, as well as a weekday vs weekend discrepancy, and a hot/cold weather discrepancy - so there are lots of timescales over which money can be made)
With SoH decreasing the internal resistance increases and the battery inherently becomes a fire hazard. At some point the energy required for cooling will not be justifiable and the battery will have to be decommissioned.