Since when is "Don't be too fool to use..." an English expression
Solution 1:
This is a broadened usage, and still, I'd say, non-standard. For the adjectival usage of fool, Macmillan adds three caveats:
fool {adjective} [only before noun] [American] [informal]
stupid or silly
- What’s that fool boy done now?
The predicative use, (as well as the graded use, as no example is supplied), is thus not sanctioned. Lexico and Cambridge Dictionary also carry the [only before noun] caveats. Though not given the explicit caveat by Merriam-Webster, only ungraded prenominal examples are given.