The hitch there is that there's not so much an ecosystem for individual Microsoft products as there is a Microsoft ecosystem, where all the products are puzzle pieces that snap into each other. So if you're in that ecosystem and a Microsoft product you're currently using stops being available, there will be a strong gravitational pull drawing you towards other Microsoft products to fill the gap. You can fight that tendency by bringing in non-Microsoft products, but even if they're much better than the MS alternatives, MS people are always going to feel weird about using them. It's like telling them to defy gravity by standing on a chair all day.
You're right. If they'd picked C# (again, in 2013 or so!), I would have been disappointed but understanding. Hey, it's not my project anymore and you've gotta pick what works best for you and your team, not to satisfy my preferences. But to finally be on an open non-Microsoft platform, and then to change back to it for VB.Net? That's just mystifying.
