There is nothing better than dipoles.

I use mag loops indoors for MW up to and including 80 meters. I make mine rather large, roughly a meter in diameter, and while using a high voltage vaiable capacitor taken from an old radio, likely double ganged, the antenna itself is not amplified. I found no need for it and routinely have a signal 40 to 60 Db above the noise floor on pretty much all the signals received in its very narrow band pass interval. Outside the interval the signal drops substatially, but one then adjusts the capacitor.

It isn't about transmit signal strength on a loop. It's about (a) the ability to null out QRM/QRN/RFI sources and (b) the actual SNR. You could be on a vertical listening to a signal with a strength of S7 and noise of S5 when the signal isn't present. Then you could switch to the loop and potentially realize a very significant different in the SNR (with the loop being better). The average receive loops sold focus a lot more on the lower bands (80/40 and maybe 160). I wouldn't expect them to yield stellar results as far as SNR goes on higher bands, since the higher bands are typically much less noisy. You should compare SNR / receivability / audio quality of 160/80/40m signals between the vertical and loop, especially weaker signals. That's just my take.

Maybe I'm missing something, most folk have noise from 40M and below, I see no use for it on any bands higher. A bit pointless really, just my thoughts 💭