Yeah would be great. I think they think not having it encourages grouping.
Since alot of groups are quest based, you at least know that they are reasonably near your level or they couldn't do the quest. That leaves around a 5 level range or so.
Personally, I always include class and level when contacting someone about a group. However, when forming a group it is somewhat blind.
The LFG menu can be used to find people. That shows class, level + location.
In one way that is eqivalent to /who. The only difference is that everyone is /anon by default and also, people aren't going to tick LFG unless they are actually looking for a group.
In daoc, spamming people around your level could get them to join an exping group, even if they weren't planning to go exping at that time

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