The choice isn't "telemetry or you're blindfolded", the other options include actually interacting with your userbase. Surveys exist, interviews exist, focus groups exist, fostering communities that you can engage is a thing, etc.
For example, I was recruited and paid $500 to spend an hour on a panel discussing what developers want out of platforms like DigitalOcean, what we don't like, where our pain points are. I put the dollar amount there only to emphasize how valuable such information is from one user. You don't get that kind of information from telemetry.
We all know it’s extremely, extremely hard to interact with your userbase.
> For example I was paid $500 an hour
+the time to find volunteers doubled that, so for $1000 an hour x 10 user interviews, a free software can have feedback from 0.001% of their users. I dislike telemetry, but it’s a lie to say it’s optional.
—a company with no telemetry on neither of our downloadable or cloud product.
On the contrary, your users will tell you what you need to know, you just have to pay attention.
> I dislike telemetry, but it’s a lie to say it’s optional.
The lie is believing it’s necessary. Software was successful before telemetry was a thing, and tools without telemetry continue to be successful. Plenty of independent developers ship zero telemetry in their products and continue to be successful.