I don’t know if this was intentional, but I’ve noticed a difference in menu item left-padding between the item icon and the item text, depending on which theme you choose.
e.g
padded (Light)
unpadded (Kde-Plasma)
This is on 22.04 and probably 22.10 (i can’t remeber 20.04).
And here is a summary;
Ambience padded
Arch-Colors padded
ClearLooks not padded
Dark padded
Frost padded
Kde-Plasma not padded
Kvantum padded
Leech not padded
Light padded
Lubuntu Arc not padded
Silver not padded
System not padded
Valendas not padded
For anyone who wants to change the padding;
Just edit the below item in
/usr/share/lxqt/themes/<theme>/lxqt-panel.qss
QMenu::item {
color: palette(text);
/* padding: 5px 27px; */
}