I really hate whenever I try to explain how some bad rules can be abused and immediatelly get someone say shit like "If this happens in your group, change it" as if that would solve the problem. And whenever it is not soemthing you witnessed personally, then it means it never happens and could never happen.
Every edition of every ttrpg has had rules that can be exploited and abused, and the solution has always been for groups to alter rules as necessary. It's impossible to make an airtight ruleset. You are just a 5e hater.
It's impossible to make it perfect, but it's trivial to make it better. For example, get rid of Silvery Barbs.
And we'd really hope with a large corporation behind it, they could do more than get rid of the obvious. They could do the playtesting necessary to properly balance martials vs casters.
That's just one spell in an optional sourcebook that's just an MTG cash-in, though. I've never been in a campaign that allowed players to use content from non-core books with abandon.