If we are honest, we can say that we just have no idea what would happen in case Lamar is forced to throw more. Sure, if it turned into 50 pass attempts for a game, we'd be totally screwed but that's no different to what happens when Flacco throws that much.
The only real measure we have are their 2018 stats. Based on them and, if we are talking more sensible balance in pass/run ratio, I'm not sure we'd be screwed any more than we'd be with Joe:
Lamar:
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Joe:
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Those are fairly similar numbers and the most interesting one to me is total yards - looks like Lamar throws more real passes than checkdowns.