Reasons :

1. The option "smiley or enter" can be found many years now in chomp sms so Delicious Inc knows exactly how to easily implement it in Textra.

2. The option "smiley or enter" does not create a problem to those who prefer the "enter". I don't ask to replace "enter" with "smiley". I ask Delicious to give users a simple but very practical choice.

3. Smileys don't spend many characters like emojis do. That's why many of us prefer smileys instead of emoji. It's the same reason we choose to strip accents and diacritics = to spend less money in messages.