>>35589685The good is heavily outweighed by the bad, which is that a staggering 7 types resist it, many of which are commonly used types.
And while hitting Ground is nice, Water/Ice are usually both prefered for the role, and have more utility. Hitting Rock hardly matters because Rock has a million weaknesses anyway.
The strongest utility Grass has offensively is that it's the only type that can switch in on water and hit back SE, but that's somewhat diminished too by almost every Water type having ice coverage, and one niche just isn't enough to justify relying on the type.