] Sure, but they don't do those things very well. That's the problem you get when everyone can do (a little of) everything. Nobody does anything particularly well.
That's what AD&D 2nd edition was for: nobody fought like a fighter, nobody healed like a cleric, nobody stole like a thief, or made things explode like a wizard, or...spoke to plants...like a druid, or whatever it is druids do. The roles were way more defined back then.