We don't know how often abiogenesis takes place, or even if it is physically possible that it can occur more than once. Therefore we have no basis for saying that it is likely that abiogenesis takes place frequently based on the fact that there are a large number of stars. That is a ludicrous non sequitur.
When people say that life on other planets is statistically likely, I tend to attribute it to ignorance of the fact that abiogenesis is not understood, rather than outright stupidity.
WHen people say things like statistically likely they are not making a positive claim. Highly likely or even extremely likely still isnt a positive claim of anything.
Probabilities are open to change with new information they are not at all dogmatic propositions or numbers. I would be in agreement with you if someone was telling that you must accept that aliens exists somewhere despite what you believe about aliens.
This is where some theists (and atheists) run into trouble, they insist that you have to believe their stories. Its ok to be confidant in your beliefs, nothing wrong with gentlemanly assertiveness. If you truly believe something why not be assertive instead of wishy washy? Of course one must accept that not everyone will agree. But if you look at this thread most of the posters are not trying to make a undeniable positive claim about aliens. Most are just saying look there is a some logic in the concept that there may be aliens out there. Mathematical statistics (which the entire concept is centered around) isnt defined as a positive claim. SO why are you pointing out the obvious here, do you think that you are the only one that knows this?