[therealdrag0]

The question isn’t “how long could a db be used if desired or left alone?”; the question is @how long does it take to migrate off if forced?”

[turtlebits]

Time is money. A migration could easily require code changes + testing, which can add up. If you're a small business that has to outsource this, I could see the cost of migration costing more than their aggregate DB hosting costs so far.