Sure thing.
Luckily, it didn't take much time to figure it out. Thanks to the person who answered here: https://unix.stackexchange.com/questions/16578/resizable-serial-console-window/283206
I was able to use something POSIX standard like the "res()" shell function he described to get it working.
I just put it in as a bash function in my .bashrc file and had it only call when "TERM=linux" which seems reasonable to me for now, since picocom (and the regular Linux pTTY) always seems to set the TERM variable to that.
resize-term() {
OLDSTTY=$(stty -g)
stty raw -echo min 0 time 5
printf '\0337\033[r\033[999;999H\033[6n\0338' > /dev/tty
IFS='[;R' read -r _ rows cols _ < /dev/tty
stty "$OLDSTTY"
echo "Set cols = $cols"; echo "Set rows = $rows"
stty cols "$cols" rows "$rows"
}
[ "$TERM" == "linux" ] && resize-term