One of the most ridiculous things I've ever heard. Also a complete failure to understand the philosophy behind the success of FLOSS.
Generic problems that are widely shared with limited variations in functional need are successful FLOSS solutions or platforms.
Specific problems that are more nuanced and meet niche requirements are what works best in commercial software.
It philosophically makes no sense to call something immoral because a subset of entities are happy to pay for it to achieve their goals. Symbiotically most FLOSS is supported by these solutions which are often based on them.