Jyutping was not taught in school, most definitely not the case when I studied primary school in Colonial HK. Wasn't the case when I went back and worked a few years, watching little cousins type their school work with something other than Jyutping. So I'm not even sure how much uptake a jyutping keyboard there would be.
For me, as someone who don't type Chinese enough that I'd struggle badly to use an IME based on strokes, I actually use a pinyin keyboard, because:
a) pinyin can be found as first class citizen on any OS;
b) for someone like me, who speaks Cantonese, and could butcher Mandarin enough to order food, and have no formal education in either pinyin or jyutping, I find it a lot easier for me to guess in pinyin than in jyutping. Most of the Cantonese jyutping (or "cantonese pinyin" keyboards) have a specific transliteration of Cantonese sounds to the English alphabet in a way that I can't grasp easily. The only exception was the Google Cantonese Pinyin IME, which was decently good at taking various transliteration that someone might try, and return a list of reasonable words. But it has since been discontinued, I couldn't find install it. To expand to why there's an inconsistency with transliterating Cantonese sounds... It's not taught in a standardize, formal manner in school, and you can see that with the author's name here, 阿擇. He has Chaaak, which to me is a transliteration pretty far off from the actual pronunciation. http://www.cantonese.sheik.co.uk/scripts/wordsearch.php?leve... suggests "zaak", while I might have attempted "zhak", or "zhaak", or "jak" with the Google Cantonese pinyin IME, with the latter a closer map to the actual sound of the word IMO. I wouldn't associate z with the start of the sound. I've seen some older methods uses "ts" instead.
c) for someone like me who struggles with writing / typing the word based on strokes, and find that IMEs like jyutping is not a great choice either, a last resort is for me to look up a word from English, and lo and behold, pinyin is most likely to show along side with a Chinese word when you try to translate from English to Chinese. This provides a convenient way for me to mentally retain a pinyin mapping to the word. Given pinyin is standardized a lot better than jyutping ever has, and the sound to letter mapping is definitely more understood to me, it's far more convenient.
I type Chinese, to my family, in pinyin. It would actually be quite nice have Cantonese word that's accessible via pinyin. It's a fucking mess to try to look up a primarily Cantonese word for someone like me, because again, there wasn't a standardized version taught consistently. And I don't find jyutping taught now.
All this just seems to me a tempest in a fucking teacup. As a matter of practicality, I'd welcome it.