A lot of Japanese learners do hate katakana (personally, a lot of fonts could stand to be clearer about ツシンソ ), because most writing is in kanji+hiragana so they have less practice with katakana. But kana ability is really just exposure. Use it to get used to it.
Same reason people say kana-only writing (like in old videogames for example) is hard to read: People competent at reading any language don't spell things out in detail, even when we subvocalize we first recognize the shape of the scribbles and our brain has a shortcut from a certain set of scribbles to certain morphemes/words, where the solid feeling of meaning comes from.
Every competent reader of Japanese is first and foremost used to the kanji-hiragana mixed script, and has shortcuts for the kanji forms of words and the sounds of those words. The hiragana only forms? Not so much. So when they complain about hiragana only being hard to read, they're not lying. It really is harder. But it's not harder due to any inherent defect in a hiragana-only script, it's just about a lack of exposure to form those shortcuts that make reading feel easy.
