I don't think there is any kind of trend towards "more idioms".
I don't know what you have in mind either when you say "idioms". Many expressions are technically speaking idioms but we don't think of them that way. If you mean the more "colourful" expressions, if you're not comfortable with them, don't use them.
As for everything else when it comes to using a foreign language, use what you find comfortable and what you understand. Using simple straight forward language will make you understood and no one will complain about that. Using idioms you don't fully understand will simply confuse the listener/reader.
I would suggest learn the ones you hear/read often. Don't worry about other ones.
Student or Learner