Development with a proprietary language is ultimately harmful to your own interests, whether you make proprietary software for a profit or Free software.
The one thing every business needs is control. When you make it possible for another company to block your business, you lose control. Your options become limited. Solving business problems potentially becomes very costly, involving a complete rewrite.
The one thing that should be abundantly clear to everyone by now is that making your business dependent on Microsoft anything is ultimately a losing proposition. They have a long history of deprecating their own products after customers have built products upon them.