Yes (although the voltage will usually be relatively uninteresting).
As you say, the pathname given by @amarok above reflects the USB PD negotiation and the negotiated maxima, not the instantaneous values.
Various people have had a hack at it e.g. Librem5 BatteryJuice measurement or Script to Play a Battery Charge Notification or Warning although I personally am using info out of /sys/class/power_supply/max170xx_battery and, yes, I don’t know what script that blog post author was using to collect data.