If you look into Lue Elizondo's, former head of AATIP, comments on this, you will come to find that he believes these things are testing are doing reconnaissance to test our military capabilities - which is scary to me.
The technology they are displaying is awesome, but it is something we should be very wary of.
Assuming this is an advanced civilisation, this seems highly unlikely.
Our capabilities can be well enough assessed from the comfortable safety of billions of kilometres away simply from watching our relentless broadcasting of them in all directions for decades if not centuries now.
We even sent out devices at the limits of our sphere of physical influence, introducing ourselves and with instructions on how to understand what we say.
Certainly, by simple initial analysis of even our most basic technology they could then monitor our own satellite networks on a whim and see all of the same things about ourselves that we do, in realtime and in totality.
Ingesting our transmissions and emissions and assessing our capabilities would be something they could do far more thoroughly than we can ourselves. They'd likely also be able to project what we'll have ten or twenty years from now in detail.
Sending a craft in can only reasonably be interpreted as "hi" given a context of technological dominance, which by necessity is founded on informational dominance.
The technology they are displaying is awesome, but it is something we should be very wary of.