Honestly, depends.

If it's at 100k tomorrow due to some big development, like USA adopting Bitcoin for its treasury, or something like that, It's just what expected of Bitcoin, so I hold, because it's going higher.

If it spikes to 100k due to some exchange bug or a whale mistakenly market-buying, I'll take a risk a swing it, selling some at 100k and expecting to rebuy at lower prices.

That being said, greed always results in less sats, so I'd always lean into holding as the safer option.