Previously, due to the differences in which text and emojis are encoded, emojis often have different character counts. The difference may be greater when gender and colour modifications are applied. This made composing tweets a little tricky, especially if you wanted to make full use of the 280 character limit, and want to have a lot of emojis as well.
With emojis having the same character count across the board, it should be easier to use emojis with any modifier you like. This is simply because you don’t have to worry about your favourite emoji with your favourite modifiers costing more character space than the defaults. (Source: Twitter)