Ghosting saves you one awkward conversation and quietly chips away at your reputation.

Disappearing is cheap now and expensive later. Going silent avoids one uncomfortable exchange, and in return the other person gets no information and tells the story of it accurately, which accumulates: a few of those and you are known as somebody who vanishes, in ways you never get to see. The trade feels good for one evening. The pricing is bad.

Send the short honest message instead, two lines with no essay attached: say you are not continuing, and say thanks. Do it the same week you decide. Awkward and brief beats a reputation you cannot inspect.