What a strange take. Why wouldn't they rather not create it in the first place if they were so worried about cannibalizing their free product by ... another free product?
The most logical explanation would be something like "they released this product because they were making a huge effort to get C# to be a truly cross platform language but the mac adoption remained low so they decided to retire this product and focus more on VS code which has massive adoption on mac"
But that would be too aligned with most developers priorities so it is not even on the radar for most people.
I think they are killing it for two reasons:
* Cross-platform .NET development on VS Code has gotten very good.
* JetBrains Rider is even better, especially for professionals, and becoming very hard to compete with.
Getting VS Code as popular as it is today was the strategy. For that, it needed to not be shitty.
The enshittification only began after they took over the market