Target Culture Failure
Microsoft have defined support statements and end of life definitions for Windows 7/8/8.1. For varying lengths of time, these OS versions will be supported for enterprise, small business and consumer users. So MS will not be able to save money by killing them off a bit early; they're contractually obliged to maintain them. Thus Microsoft's desire for Windows 10 upgrades is about numbers and market share, perhaps a bit of esteem.
We might also conclude that the decision to change dialog box behaviour was not taken at board or CEO level. We should assume that a Windows 10 Upgrade group was told to persuade users to adopt the OS. Somebody will have plucked target numbers for adoptees out of the air and somebody else is trying to meet them, whatever the reputational risk to the company.
All that needs to change is for somebody at board or CEx level to see the damage that is being done. Reporting of recent actions in mainstream media -- not just geek press -- has given MS a well deserved kicking. I presume execs can read and understand that their messages and signals about upgrade targets have been misunderstood by company employees lower down. They need to apologise honestly about company behaviour and rethink target culture.
It's not hard to do. Tens of thousands of Windows users -- small business people, families, IT professionals, other professionals -- have been telling Microsoft. But it takes humility and courage to admit what has gone wrong.
Disclaimer: Most of the MS software engineers, sales support workers etc who I've met are good people, even when they're looking at a problem the wrong way. I usually like working with MS people. But when you meet a Microsoft employee who isn't listening, walk away and talk with somebody else.