Tardigrades are quite durable otherwise.

only in their dried-out state. Under regular conditions, they are easily squished.

OK, how? All the photos I've seen of them are taken with SEMs, implying that you can't squish them any more than you can squish an amoeba.

I work with live tardigrades under a microscope and you could easily squish them with a little metal pick, or by pressing on the glass coverslip.

Tardigrades are very different from amoeba. They have a well-defined cuticle exoskeleton surrounding a liquid space, about 1000 cells, while an amoeba is single cell and highly deformable.

Ahh, I thought you meant with your fingers or something, that makes sense.

I suspect if you really tried to deposit a pile of tardigrades on your finger and squeezed really tight you could probably damage them with the ridges of your fingerprints. I don't know enough about the biophysics of finger pressure and how the surfaces interact, and I wouldn't really want to do this (feels cruel, even if they have very limited nervous systems).

Yes, durable enough to power FTL starships in the future!