On-prem SQL Server instances in large organizations are typically treated by accounting as a capital expenditure (CapEx), so there is a financial motivation to hang onto it for 10 years (or more). I mean, the longer they go without upgrading the license, then the better it looks on their financial statements from a ROI perspective. However, those of us in IT know there are both financial and opportunity costs involved in not upgrading (extended support, missing out on new features, less scalability, the best DBA talent moving on to other things, etc.).
"Do not seek to follow in the footsteps of the wise. Instead, seek what they sought." - Matsuo Basho