Until we have conclusive proof that life of any kind exists beyond Earth, we have no solid foundation from which to extrapolate meaningful statistics.

2 hours ago, DD_Arthur said:

In a galaxy of upto 400 billion stars...just us? It seems unlikely....🤷‍♂️

The transition to multicellular life is regarded as momentous. Some experts suspect that the vast majority of life out there is just single celled goo. In the history of our galaxy there may have been a number of technological species, but whether any of them are around at the same time as us is the question.

There are some researchers, however, that suspect the transition might not have been as momentous and rare as we believe.

Basically, we have no idea but it isn't out of the question that, currently, now, at this precise moment, we are alone. We can't rule it out.