here is an article detailing how left wing activists petitioned to have their meaning of the word added to dictionaries in 2013.

https://www.huffingtonpost.co.uk/claudia-white/transphobia-is-in-the-dic_b_3651053.html

9 years is a very short for the life for words. So yes, it has been recently changed by left wing activists trying to control language. And it didn’t used to mean that.

And here is an 1992 definition, which means irrational fear, aversion, or discrimination. Note there is no hatred, or bigotry involved.

https://www.merriam-webster.com/dictionary/transphobia