The issue lies with each individual customer’s perception and knowledge of Windows 7 vs Windows 10.
The bottom line is that we all know that Windows 10 beats Windows 7 hands-down.
However, those that use bespoke applications will be reluctant to migrate, especially if their application works well and/or they do not have the resources to port it to a later version of Windows (or the code simply cannot be ported). Then there are those who are of the opinion that a migration to Windows 10 will be fraught with problems – particularly considering the poor press Microsoft has received over its feature updates despite Microsoft’s assertion that a very small percentage of customers have been affected (and support for updates is free).
Taking an aggressive stance on anything always gets people’s backs up. Perhaps Microsoft will take a gentler approach this time.