Some people like ligatures, some people do not like them, but this does not matter, because any decent text editor or terminal emulator has a setting to enable or disable ligatures.
Any good programming font must have ligatures, which will keep happy both kinds of users, those who like and those who dislike ligatures.
I strongly hate the straitjacket forced by ASCII upon programming languages, which is the root cause of most ambiguous grammars that complicate the parsing of programming languages and increase the probability of bugs, and which has also forced the replacement of traditional mathematical symbols with less appropriate characters.
Using Unicode for source programs is the best solution, but when having to use legacy programming languages in a professional setting, where the use of a custom preprocessor would be frowned upon, using fonts with ligatures is still an improvement over ASCII.