Great questions! • I have never heard "ramp out" before. Perhaps you meant "ramp up" which would basically mean to increase, especially for the activity of a business. Let's ramp up production of clear phone cases—people want to see their devices! • "cash in on" essentially means "take the benefits of." This might also suggest what we're doing is unfair. Someone might cash in on their viral video by finding a way to monetize it further (e.g. that grumpy cat which became a brand). "Exploit" or "leverage" are helpful close synonyms. • to sideline someone is to stop them from participating in something; in sports it is to stop a player from playing. Sasha was sidelined after she called out the company for fraud. Jerry was sidelined after failing to score any goals in the first half of the game.

"Sideline" or "side gig" can also be used to describe something a person does in addition to their regular occupation. For example, I teach as a profession, but my sideline is making and selling jewelry from shells I collect on the beach. (I wish!!)

Rump out sounds to "run away from", "cash in on" sounds to take benefits from as said below, "sideline" is often heard in "seen from the sidelines" it's something not seen or heard directly but from from the sidelines (from the sides / out of it)