top with USE=+modern-top (package procps) shows incorrect memory usage. To reproduce, toggle with E through different units (MiB, GiB etc). The value does not change. Tested on x86_64, arm/rpi. FYI: procps states to contact the distributions first. Reproducible: Always
Please post the output of emerge --info procps
Sorry, this is invalid. I misinterpreted the mem usage value which turns into a percentage value in certain views (when toggling with m towards the 'summary line view').