You are conflating two separate things, a product does not need telemetry to function and if telemetry is needed it can be opt-in. Similarly a product does not need to be free to have telemetry nor does it need to be paid to not have telemetry, as i already wrote these two are completely separate.
> Such people would be vocal against paying for the work others do.
Again you are conflating two completely separate things: people being concerned about the privacy implications of telemetry (both directly and indirectly, see below) and people who are against about paying others for their work.
> Also, if properly anonymised, telemetry isn't the devil people make it to be.
Even if anonymized (which is something you can only guarantee for open source projects that either you or someone you trust has checked they do such anonymization properly - and also you either build yourself from the source that was checked or you used a binary from a reproducible build) having telemetry in place still creates and reinforces a precedent of it being acceptable which in turn can be used to excuse other programs doing the same but those programs actually not caring about doing proper anonymization (at best) or even outright spying on you (at worst).
Besides anonymized data can still be used in conjunction with other data to be deanonymized and the best way to protect users from this is to not collect that data in the first place.
That said, nothing wrong with being vocal about privacy and high standards in collecting usage.
Yes, I could pay them to get a product that lets me disable telemetry. I'd much rather just use something else, so I don't have to fund their unethical business practices.