I'm a Plex user, but let's not be naive. They are a business and a cloud-based subscription model is way more profitable than giving away software for free to let people stream from a local server.
You can't blame them for making logical decisions for the health of the business (even if they negatively impact you).
I would agree with you except they already get my money; I'm a Plex Pass subscriber and have been for several years. I understand them wanting to monetize the platform further, but don't do it by collecting telemetry, especially viewing habits, and potentially selling it to anyone with deep pockets (I get that their privacy policy as of now says they don't, but privacy policies tend to change once enough valuable data is siphoned).
You can't blame them for making logical decisions for the health of the business (even if they negatively impact you).