The evidence does not support the claim. Multiple recent, independent news reports document that Talarico has publicly denied being vegan, and coverage of his campaign trail meals describes him eating meat, eggs, and other non-vegan foods. The claim appears to stem from misreading a past campaign purchasing policy as a statement about his personal diet.
Caveats
A campaign policy to buy vegan products is not evidence that the candidate personally follows a vegan diet.
Some widely shared clips and posts repeat the allegation without verifying it; recent independent reporting contradicts them.
The strongest evidence is recent and specific: public denials, a spokesperson’s clarification, and multiple reports of non-vegan meals.