When consent is granted, page_view hits and key events that were previously denied are automatically redispatched to the server-side Google Tag Manager endpoint. This is particularly for the benefit of Google's advertising tags such as Google Ads conversion tracking and remarketing.

The automatically redispatched events can't be used for GA4 data collection because they are blocked programmatically from activating GA4 tags in the server-side Google Tag Manager. This is likely to prevent the collection of duplicate hits to GA4, as GA4 has its own mechanism to reprocess hits once analytics_storage consent is granted.

To prevent the automatic redispatch of events, you must not set ad_storage to granted. If you are not collecting any advertising data on the site, keeping ad_storage in a denied state will stop this behavior. However, if you are collecting advertising hits client-side, you will need to grant consent for ad_storage, which will trigger the redispatch.

Google Ads' client-side tags have a mechanism to automatically redispatch hits that were originally collected when consent was denied, as soon as consent is granted for ad_storage. This is because Google Ads does not have a similar mechanism for reprocessing hits as GA4 does, and it ensures that advertising tags can still function and track conversions.

According to the current understanding, this behavior cannot be modified. Attempts to use a transformation to change the behavior, such as stripping out key parameters controlling it, have been unsuccessful.