Any day, I (as a manager) would prefer to have an experienced Developer do a Production Support role, rather than a cheaply obtained non-engineering campus graduate hired as "Tech Ops" resource to do Production Support on complex, mission-critical systems.

It is a bad idea for a company to give shoddy after-sales support to customers, because they would then lose the customer's trust and relationship in the long run. No customer wants to see their production systems have frequent incidents caused hours or days of outages.

Vendor companies ignoring investment and support for Production Support on their Products/Services, do so at their own peril.

In fact, canny companies have realised the real money is not in upfront cost, but in volume billing (billing/invoicing, based on monthly transactions counts, number of users/licenses and tiered rate card), so they need to have adequate Production Support teams

This is why companies are trying their level best to move existing customers to subscription services (e.g., Office 365 by Micro$oft).