When online chess became super popular during the Covid lockdowns, FIDE fielded a number of requests to allow titles to be awarded based on online play. Thankfully this push was resisted, in part due the fact that online ability and OTB ability can be two entirely different things.
One of the reasons I gave at the time (when I gave my 2 cents worth) is that becoming an IM/GM due to an opponents mouse slip or technical issue just didn't seem right. Of course it could be argued that an opponents horrible blunder, or mid game medical emergency might be the real world equivalent but I am going to say no (in part as now 4 things are on the list of 'unfortunate events'). This has recently been shown in a couple of games in the esports games, which are currently running.
One match was simply decided by a mouseslip after 1.e4 e5 Nf3 Nc6 3. Bc4 Nf6 4.Nc3 Nxe4 5.Nxe4 d6?? (instead of d5) 1-0
The other involved a (assumed) pre move blunder, where Player A expected a certain move and premoved the reply. Player B chose a different move and the premove was a complete blunder in a winning position. While blunders are a part of chess (and Player A should have know better), 'pre-move' traps are common in online chess (at bullet especially) where a player assumes a reply, and then plays an inferior move to exploit this. An obvious example (which also happened in CC) is when a player is known for 1 ... b6 and 2 ... b7, so White starts with 1.e4 b6 2.Ba6??!! Bb7 (premove) 3.Bxb7
It might be fun, but it isn't really chess.