Now that I'm looking into it, you're right, they look exactly identical in most fonts, which I'd never actually realized! I don't think it's a simplified/traditional thing -- I think most fonts just aren't bothering to differentiate them? Here's a comparison in DFKai font, which does distinguish:



Wiktionary says "These may be written identically as 月, but in careful use they are distinguished, with the inside of ⺼ being written with unattached diagonal strokes." I think I learned to write it that way when I first practiced radicals on Skritter, and just assumed it was always supposed to look like that -- I thought the diagonal lines just looked straight in small font sizes! (Another thing learned today! XD)