Marketo forms will still submit data to Marketo even if the Munchkin tracking script isn’t loaded. The difference is that, without Munchkin, you won’t capture web activity or tie browsing behavior to the lead record.
Many organizations handle this under GDPR/CCPA by conditionally loading Munchkin based on consent. That way, form submissions continue to work regardless of consent, but behavioral tracking is only enabled when the user has opted in.