xubuntu 18.04 vs 20.04: same font displayed differently

I'm trying xubuntu 20.04 prior to fully migrate from xubuntu 18.04. Almost everything looks fine and running smooth, except my favorite XFCE desktop font's appearance. In 18.04, I modified a gtk-2 theme and use Arial MT Medium (opentype) font for desktop icon-label. I know that 20.04 comes with gtk3 theme, and in 20.04 my gtk-2 theme becomes so ugly. So, I translate any possible part of gtk-2 theme into gtk3 and so far so good, except that one, desktop icon-label font.

here is the comparison

in 18.04, the font looks very good, solid and brightful in white color. While in 20.04, to me, it looks like not being anti-aliased. Can this be fixed? thanks in advance.

Over a year I left this off. Now, I'm back with a solution.

I simply :

1. copy ArialMTStd-Medium.otf font to /usr/share/fonts
2. fc-cache -f -v
3. set XfdesktopIconView.view { font-family: 'Arial MT Std Medium' } in my customized gtk3 theme :)
4. refresh current theme

Now my favorite desktop-icon label font is back in Xubuntu 20.04

edit:

my bad, forgot to embed the final result

enter image description here