That's what I don't get either. If they can shove off one of their top 1500 customers (probably much higher) and, as someone put it, "everyone is using them", that means unless you're one of the top few hundred customers, this can absolutely happen to you. Which is what people are upset about.
And the risk they're most concerned with is the business ceasing to function.
I worked at a F500 that used VMWare; they'd probably pay a 12x subscription fee. Not because they want to, but because they started trying to get rid of their mainframe 30 years ago and 70 something percent of their business still relied on the mainframe last I was there a decade ago.
VMWare will likely go the same. It'll take them a year or two to PoC an alternative and get contracts signed, another 5 to move the low hanging fruit, and a decade to finish off the long tail of stuff that won't migrate easily.
We're talking migrating stuff running versions of Java that were EoLed a decade ago, using an app container (like Tomcat) that was also EoLed a decade ago, and trying to get that all working on a new infra stack.
And it's not just one of them, there are thousands of apps, many of which are outdated or have bizarre vendor requirements you'd likely never accept (like "we will not support you if you run this bog-standard Django app on a VM").
Stuff like this moves slooooowwww, especially at companies who only use tech to enhance their primary business (as opposed to tech being their primary business).