This is nonsensical. Even if you're right, then most people who don't want cryonics are just mistaken about the probability of success. Being mistaken about something cannot be either suicidal (in the ordinary sense) or selfish, since both of those require conscious decisions.

If you think a bridge is safe, drive over it, and fall through to your death, was your decision to drive over the bridge "selfish"? Of course not. It caused pain and grief for the survivors, but not knowingly.

PS: What's your estimate of the probability of success for being rescued by time travellers if you make sure you die in a closed vault so you can be rescued without changing the past?

85%? Seriously???

The near-certain impossibility of anything resembling the molecular nanotechnology favored on that page alone blows that out of the water as does the severe apparent institutional incompetence of cryonics providers.

deciding against cryonics [..] causes pain and grief for the survivors

I don't expect that my friends and loved ones will experience less pain and grief when I stop breathing, talking, thinking, etc. if my brain has been cryopreserved against a possible future when its information-theoretical content can be extracted and those functions re-enabled, than if it hasn't been.

So if my deciding against cryonics is selfish, it is not for this reason.