OLED screens consume more power than an IPS screen, unless you display only black pixels on the screen. Explain to me by what miracle the autonomy would be greater?
I find the desktop useful, more software means more possibilities and more drivers for external devices. In any case, it covers my needs better.
Privacy is not a strong argument. And I am very concerned about this issue. You can disable the telemetry with a little bit of tuning in Windows and you can block the traffic with an FW. Privacy is systemic and not just Windows. Look at your phone, bank, connected objects, TV, insurance companies, … Do you think steam is not spying you ? Have you read their subscriber agreement ?