> If Tesla offered $10/month charging for your Tesla
No, "if Tesla offered $10/month for 100 kWh of charging", and yes, I expect to use those 100 kWh with any vehicle I want, because there's a limit on the resource I'm paying for.
I can understand caps on unlimited, I can't understand caps when there are strict limits.
You are the reason these changes are happening. You may well be the reason that subscription prices go up.