Tracking without cookie consent

In addition to what @jennifer_dungan said -

If consent for analytics cookies is denied, tracking becomes very limited. Without cookies or persistent IDs, each pageview is treated in isolation or at best tied together only within a single session if session-based logic is allowed.

1. Visits can still be tracked if a temporary session ID is maintained, but those visits won’t connect across sessions.

2. Unique Visitors cannot be reliably measured, what you’ll see instead is inflated counts, since the same person looks “new” each time they return.

3. Yes, the aggregate visitor number will be overstated for that reason.

4. Engagement within a visit (like multiple pageviews in a single session) can still be tracked, since it doesn’t depend on long-term identifiers.
   
   

In short, you can still measure visits and session-level engagement, but anything requiring persistent identification (like Unique Visitors across days) becomes unreliable without consent.

So as far as I understand, cookie consent is different from all out "tracking consent"... though most companies seem to bundle these together (incorrectly as far as I am concerned).

When someone opts out of Advertiser Cookies, they still see ads... they just don't have cookies tracking their behaviour between sites, so if you were looking for shoes on Site A, you won't get ads for shoes on Site B, but you will get generic run of site ads....

This should mean the same applies to Analytics... if someone opts out, well then you need to make sure the cookies only last the session, then expire (the session should maintain the same user as they travel page to page, but the next visit they will be treated as new).

In AppMeasurement, this is easy to do... the ECID extension has opt-in/opt-out logic, that should prevent an ECID from being set (following the user between sessions), and you can set the fallback s_vi cookies in the Analytics extension to expire after session.

WebSDK however, seems to be all or nothing... which I think is a massive miss. I don't think you can control the cookies granularly to allow tracking, but not follow the user between sessions (unless something has changed). I am not even sure how much custom effort you can do, since there are server side cookies set to identify people....

That said, assuming you are on AppMeasurement, and have configured your cookies according to your policies:

1. Can Visits still be tracked?

Yes, Visits should still continue to track

2. I understand that Unique visitor might not get tracked but can an aggregate number of visitors be ascertained?

Technically yes, but it will be inflated... the same way that any user who clears their cookies manually after each session would be treated as new on each visit

3. Would number of visitors be an inflated number?

Yes

4. Deeper engagement tracking for example, users that have engaged for over 2 pages in 1 visit, can a metric like so be tracked?

You should still be able to do this, since you would be looking at Pages in a Visit... since these shouldn't be impacted, you should be fine.. it's really UVs that are going to be the gotcha.

On that note, in our consent model, since we don't required analytics cookies to be opted out, we are going to set our messaging to clearly show that Analytics cookies are part of our required features... that said, if we were allowing opt-out, I would probably set up a dimension to track "opt-in" or "opt-out" on each call, so that I could segment based on the status, and use UVs against the more reliable opted in group...