In general no, unless asked the dealer shouldn't touch or count the chips. While not a hard rule or anything from what I can recall, it's better to just wait until asked. Some players like to use speech play and interact with the all-in player. I've seen some players get very upset when a dealer has just dived into counting the chips.
It's not a hard rule from what I can remember, more so just giving the players an opportunity to play their game how they want. Some players will just ask for a count straight away and in which case just dive in and count it out. Just remember though some casinos have house-rules and yours may have a rule that requires it to be counted out. Just check if unsure with the cardroom or casino.
It's also potentially time saving for the game. An example of this, Player A goes all-in for a lot, Player asks how much is that, before the dealer can reach for the chips, Player A says some big number, Player B just instantly mucks.