Only to confirm your impression, but on the very opposite side of the spectrum (low power machines, where a comparison is more likely to show noticeable differences).
I just got two extremely el-cheapo (and old but in themselves "good enough") netbooks, identical, Asus EEE PC 12.1" 1201T (a not-so-common model sporting an AMD MV-40 processor).
These machines are (were) intended as "pure" netbooks, i.e. minimal browsing and "normal" everyday activities in a rather light and portable format with a several hours lasting battery.
Put on them both the max RAM (2 GB) and new 240 GB SSD drives.
On the first I restored (from recovery partition) the original OS (Windows 7 Home Premium 32 bit), which I then updated to SP1 and via Windows Update to an as much "current" situation as possible.
On the second I experimented an install of Windows 10 home (last release 2020, directly from MS original iso).
I won't detail the amount of troubles I had to actually install the stupid Windows 10, as it would become a rant, but trust me it wasn't easy (on the other hand in the Windows 7 one having to deal with Windows Update (non)response times has been as well really trying)
Anyway, after having run them both a few hours and having let them "settle", I briefly tested the two PC's side by side (literally).
Quick sum up:
1) booting times: Windows 7 is seemingly a tadbit slower to get to the desktop, but Windows 10 is "faking", if I count the time until the Start button responds, W7 is faster
2) CPU usage: Windows 7 uses far less CPU at rest (including running in the background some of the built-in ASUS tools), W10 has a sh**tload of processes eating CPU time
3) RAM usage; Windows 7 at rest is around 532 MB, W10 at rest is around 1.1 GB (more than double)
Right now I am re-setting/re-installing the second netbook to Windows 7, and make it identical to the first one.
jaclaz