This was cited in Guthrie’s Guide as an example of bad business jargon, without much additional commentary.
Because of its ubiquity, this dreadful phrase merits a few words.
Ubiquity, for starters. The phrase appears in nearly 5,000 posts on Lexology, which to me suggests one word: hackneyed (and therefore to be avoided).
It’s also unnecessary, as there are perfectly good, plain alternatives: lessons or important points come to mind (but, please, not learnings).
And if you have readers in the UK, you may occasion some scratched heads: a takeaway is a take-out meal or the establishment from whence it came – so your reader in London may be wondering, ‘Does she mean “really important curries”?’