Translation:Don't you think that a billion is too much?
I disagree, I think it's often not necessary in writing as well (see what I did there?).
I wasn't able to find any sources that supported your opinion after a cursory check, but here's one that supports mine: https://www.quickanddirtytips.com/education/grammar/when-to-leave-out-that
Should be accepted, but:
Too many - when you talk about an quantity (discrete)
Too much - when you talk about an amount (continuous)
you won't say "too much people" but "too many people", and on the other hand, you won't say "too many water" but rather "too much water". So that being said - I can't think of a situation where you count a quantity of something in billions, it should become an amount way before.
Money is a collective noun. We could not say "too much dollars" but would have to say "too many"; on the other hand, we could not say "too many money" but would have to say "too much". Therefore, a billion could be either too much or too many, and BOTH should be accepted. A billion is too many dollars or a billion is too much money!
What's wrong with "more than enough"? yoter = more, m = than, dai = enough. In English they are almost identical, altho there is a slight nuance in that 'too much' is often critical whereas 'more than enough' is not condemning the person, just telling him that he can stop now. If this cannot be translated "more than enough" how would you say "more than enough" in Hebrew?