I think there is a good chance that within 100 years we can show there is life on other planets.

telescopic imaging will be very advanced by that time and we should have some massive scopes in space by then. Considering the technological advancements we have made with optical imaging it seems to be logical that we may actually be able to see them before we hear them.

I would also assume that any tech civilisation which has a few thousand years evolution on us could be looking at us right now. So if they were say 100 ly away they would be watching earth in 1907 at the moment. Theortectially it is possible they could be looking at images of the objects, people and cities.

They would know we are developing. Even a tech civ 300 light years away may have enough optical maginification power to see what we were doing before the industrial revolution.

I dont understand why we think communication necessarily happens through radio waves. It seems a rather immature assumption.

I really think optics will become our format of exploring the universe and getting close ups of planets. If we can read their road signs we can learn just as much as through two-way communication. We just need telescopes that are hundreds if not thousands of times more powerful than we have today.

I am not aware of any physical limitations to optical advancement as long as we are prepared to build massice space telescopes. Theoretically we could build one the size of a planet in space. That would enable us to see a hell of alot and with very high degree of detail.