Once calligraphy/handwriting is involved, the situation on the Western side is not much better either. Modern Anglosphere children probably would struggle with 19th-century cursive like https://www.pinterest.com/pin/375276581427478862/ ; in Germanic countries, the handwriting system underwent deeper changes, so nobody apart from selected nerds and antiquarians can read Kurrent as in Goethe's letters - https://commons.m.wikimedia.org/wiki/File:Goethe_Brief_(nich... - or even the newer Sütterlin. Contra what some posters here claim, Roman cursive (https://en.m.wikipedia.org/wiki/Roman_cursive) is right out. I don't think this should be conflated with the question of whether the writing system is understood by future readers - as an imperfect computer analogy, an ASCII text document is in some meaningful sense more futureproof than an Autodesk Animator .FLI, even if the former is on a five-inch floppy and the latter is on a USB thumb drive.

(As for the effects of the Japan's Chinese character simplification, I think they are a bit overstated. I accidentally bought a 旧字体 copy of Mishima's Haru no Yuki at a book sale once, and at least as an L2 speaker I didn't find it particularly more painful to read than I find unmodernised Shakespeare as an L2 speaker of English.)