Personally because hydro can be automated far more easily than a soil setup. Even if you just have a webcam looking at the right meters for PH and EC you can monitor it from miles away.
I visit my plants roughly every two weeks, see that they are doing as well as I knew they were from looking at the readings remotely, top up buckets for the automated dosing if needed, then leave. I cannot think of a system with lower maintenance.
Right now from my chair I can see that over the last week my tank temperature has stayed between 21 and 22c, TDS has ramped from 580 to 605 which is what I set it to do, PH has stayed between 5.65 and 5.7 air temp has stayed between 22c and 28c and RH% has stayed between 48% and 57%. I have noticed that over the last 7 days my plants have switched from high humidity at night to high humidity during the day so that means they have started to fill the space and soon it will be time to fit the dehumidifier. I will probably go do that next week.
Done right a hydro system is far far less maintenance than a soil system. Done wrong it is far far more maintenance.
We just need to help remove the ball ache from the system for @bozrdang and they will have the low maintenance system they need.
Personally, I do not use any medium because of issues like it affecting PH, being a home for pathogens etc.
If you want a truly inert medium, go for none. I would advise no medium for NFT, DWC etc.
For your little one there, it seems they did not have enough root out of the cube before being put into a system with full nutes.
What I would do (which may not be what you prefer) is to put it into a small bubbler system so the roots can become stronger and the plant larger so it has more of a buffer to handle transplanting and nutes then transplant it into whatever system you want to run.
I would start at about 100TDS over your water just so it has some food and ramp it up as you see the plant respond.
With the plant in a bubbler it is easy to check root development.