[inlineint]

> But if there are thousands of different such "surprising-to find-particles" to possibly detect, is it actually surprising to observe one of them?

It is hard to correctly identify what exactly particles from those possible thousands are observed in given data. The are two main problems: the properties of those not yet observed particles are not well known (because it is computationally hard to predict them from the standard model) and because the number of useful events is much much smaller than the number of events that correspond to already known events.

> So do elementary particles decay or not?

I don't see a contradiction here: the first generation of elementary particles does not decay (or has not been observed to decay yet), Higgs boson is not from then because the author of the answer are talking about the first generation of fermions and Higgs boson is not one of them.

[nonbel]

Thanks, I missed that "first generation" detail.