They, their etc. is the modern gender neutral personal pronoun. I don't mind it, as it serves a purpose.
But sometimes I DO mind these modern changes. Over here in Australia they have invented a plural of a plural, ie 'youse'. This means 'you' when there is more than one 'you'. 'You' is of course both singular and plural these days, even though it was exclusively plural when we still used thee and thou. 'Youse' may be useful, but I don't like it!!
Another useful but horrid modern word is 'innit', which seems to be used in the UK as a sort of 'n'est-ce pas' or 'nicht wahr' equivalent, even when its full form, 'isn't it' is not appropriate. I don't like this usage either!
Clearly our reactions to these modern usages are purely personal. I think we are stuck with them, like it or not.
Which leads me to the word 'like', which is used to signal a quote these days, by people younger than 40. I truly hate it!!