Middlebury’s Class of 2024 mid-50% ACT for enrolled students per the 20/21 CDS was 31-34, Class of 2025 was 32-34.
I don’t think the decision is black and white, but I would lean towards OP not submitting a 32 for Midd (admitted student scores were likely somewhat higher than those of the enrolled students above). I couldn’t find admitted student test ranges for the last two years at Midd on a quick search).
This is the analysis that OP has to do for every school they apply to. The fundamental question (and the answer may be different by school) is does the score strengthen the app? If it doesn’t strengthen the app, why send it?