Quick answer
Right sentiment, wrong volume, wrong hour. The verse is funny and it is making a real point about timing.
Read both lines
Everything in the first line is good on its own. Blessing a friend is good; enthusiasm is good; rising early is praised elsewhere in this book. Stack them wrongly and the result is a man shouting a blessing at dawn through somebody's window.
The second line delivers the verdict with a legal word, counted, the same kind of reckoning language used for debts: it will be reckoned to him as a curse. That is the joke and the teaching together. The saying is not about insincerity at all, which is what makes it useful. A thing genuinely meant, delivered without any attention to what the other person needs at that moment, arrives as its opposite. Chapter 25 said the constructive version at 25:11, where the value of a word is in its fit.
Related: Proverbs 25:11 · Proverbs 25:17 · Proverbs 25:20 · Proverbs 15:23
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.