Note how many people still happily run Win 7, and before that happily ran XP, and before that happily ran win2k — while being very reluctant to upgrade.
It's corporations that need upgrades and support. With corporations, I'm sure, MS is not lax and enforces the licensing policy.
Microsoft doesn't need to, AFAIK pirated copy don't get upgrades and genuine HOME copies only work on the first computer they are installed on.