Buzzwords, cliches, and adverbs are all things that can be categorized as fluff.
Fluff is the filler that goes between the ideas that add value to the email. It can be as obvious as starting an email with "I hope this finds you well". It can be less obvious such as starting a sentence with "I think". (If you think it just say it)
The less obvious fluff are words and phrases like data-driven, strategic, etc. This might ruffle feathers, but these words don't add any concrete understanding.
Adverbs and hedge words are a different type of fluff. Sometimes they're needed. A well placed hedge word can *sometimes* create the right amount of uncertainty. Adverbs on the other hand are more likely to be unneeded fluff. Adverbs like "very" are used to add emphasis, but there is likely a better word to use.
Use them sparingly.
Know your audience, but whatever the buzzword/acronym/phrase, it can likely be stated in plain English.
Avoid them. If your reader doesn’t know the term all you end up doing is confusing them. Or worse, you'll make them standoffish because you made them feel out of the know.
When's the last time a fifth grader talked to you about "synergy" or started dropping acronyms?