You're conflating two things. What we're talking about is holographic avatars REPLACING the artists at a concert. The Gorillaz band members are absolutely at their live concerts. The Avatars are for music videos, and sometimes make an appearance on video screens as an augment to their live performances.
There is no KISS thing yet. The whole story is that KISS has proactively given their label permission to do a hologram of them when they’re done touring.
No other artist has done that while still alive (according to the article).
2pac: https://www.youtube.com/watch?v=kCRaElPN5pY
MJ: https://www.youtube.com/watch?v=Q5OnW06m0Jk
Gorillaz:
https://www.youtube.com/watch?v=WIZW4SGVbhA
https://www.youtube.com/watch?v=c9RTJIrM57o