MS SQL Server was a cheaper, friendlier plugin replacement for Sybase in the early 2000s.

I built apps in an active-active bidirectional replication telecom Sybase environment and was deeply involved in migrating it to MS SQL server in the early 2000s. I remember a fair amount of paranoia and effort around the transition as our entire business and customers' phone calls depended on it (for "reasons") but in hindsight it went quite smoothly and there were no regrets afterwards.

The Microsoft went and added a nice BI stack to the whole thing which added a new dimension of value creation at a new low price point.