Windows, its default, used so much memory that there was not much left for apps.
Ubuntu used 500MB less than Windows in system monitor. I think it was still 1GB or more. It also appeared to run more slowly than it used to on older hardware.
Lubuntu used hundreds of MB less than Ubuntu. It could still run the same apps but had less features in UI (eg search). It ran lightening fast with more, simultaneous apps.
(Note: That laptop's Wifi card wouldn't work with any Linux using any technique I tried. Sadly, I had to ditch it.)
I also had Lubuntu on a 10+ year old Thinkpad with an i7 (2nd gen). It's been my daily machine for a long time. The newer, USB installers wouldn't work with it. While I can't recall the specifics, I finally found a way to load an Ubuntu-like interface or Ubuntu itself through the Lubuntu tech. It's now much slower but still lighter than default Ubuntu or Windows.
(Note: Lubuntu was much lighter and faster on a refurbished Dell laptop I tested it on, too.)
God blessed me recently by a person who outright gave me an Acer Nitro with a RTX and Windows. My next step is to figure out the safest way to dual boot Windows 11 and Linux for machine learning without destroying the existing filesystem or overshrinking it.