Do you think there is a chance that using telephone/modem wire and RJ11/12 connectors as the signal wire for WS2812B makes sense for making the installation easily re-connectable (in case of maintenance)? Any more reliable options considering the cost while still keeping the ability to connect/disconnect daily?
Power will be supplied separately near the strip using adapters.
I am reading/watching this article/video: Data Signal Cable Conditioning - quinled.info
If I have the data and ground (to have a common ground between the power-supply and ESP32) close by, would it affect the data signal too? I am assuming not because this ground cable next to the data signal is not carrying back power for the LEDs. Please correct me if I am wrong in my understanding.
Generally, the size of the data wire is not critical as there is no significant power required on that line.
Telephone/modem wire can be a reasonable choice depending on length and routing.
I would use a pair of wires for the removable connection, one data and one ground.
That will ensure the data signal is always referenced to the same ground level as the ESP source.
While the power line ground should be at the same voltage ( 0V ) it’s possible for small differences to occur when the LEDs draw large amounts of current.
A more critical item will be the length of the data cable.
The longer the cable, the more likely it will act as an antenna and gather noise on the data line.