Benjamin P. wrote:

So based on what we know is the radio waves are the most
logical wav the ET will try to contact earth.

I don't actually think seti is about making contact as such. Just looking for evidence of ETs. Thus if we detect artificial signals then we know that there exists (or existed) ET.

Contact via radio may be impossible due to the times involved. Radio is not instant, there is a 1/4 to 1/2 second delay in transmitting signals, via satellite, from the UK to Australia. Just imagine the delay over a few light years.