[Pharo-users] Is this really a string concat error?

I looked at changing the threshold of getting the string concatenation critique and got a mixed reaction, having lived with the current state a bit longer - I’m getting tired of the kind of error, but though it worth checking - do we really consider the following a warning? To me its wrong joining 2 stings with , is surely fine? In fact a stream seems overkill or surely the compiler can generate the optimal code for me? This smacks of old days where everyone was busily doing a == b just because it was supposed to be faster until the vm guys just sorted it out?