Today is the day of seeing -phobia used for hate and discrimination, isn't it.
- it takes responsibility from the ppl doing the shitty thing (yes, _especially_ if you're going to argue "it's not referencing mental illness, it's like in 'hydrophobic'!" - oppression is not a force of nature) and misrepresents the mechanisms
- it's awkward to throw people with phobias in with all that
- it is often used to score easy points from more openly ableist beliefs, see "homophobia can be cured" etc.
examples of ableist language
I mean, these are cosmetic changes that come from the idea that most people don't actually mean it that way. Just like with other changes of that nature, like avoiding calling people/things idiots, stupid, r*t*rded, schizophrenic (in the meaning of "contradictory" or whatever), crazy etc, if one's simply looking for a way to express an actual ableist sentiment behind it in less offensive words, that's still shitty.
Admittedly, German has an easier way out by simply using -feindlichkeit instead, but there are ways to do this differently in English as well.
Sadly my English is a bit shit and I don't have any idea which of the more often-propsed alternatives actually work well, but they're out there :)