installing an optimization plugin made my site slower?? lcp regression on the main headline

I did everything teh optimization guides recommended, including installing an optimization plugin... the result:

LCP is worse than before, and the report points at the main headline 😂 It feels like the optimization made things slower. Is that possible? Id like to keep teh benefits of the change if I can, but I clearly need to handle the main headline differently. Id appreciate tips that dont involve throwing away teh whole change. im about to throw this thing out the window lol