The fact of the matter is, Google Analytics has changed in the past few years in ways that make the differences between it and Adobe fairly negligible. Yet, the following myths persist:
You can capture more data points with Adobe than with GA
While you have unlimited custom data points with Adobe, that doesn’t mean there isn’t a workaround with GA. Yes, GA only allows you to have 20 custom data points. I don’t think that’s necessarily a con since it forces you to create an approach instead of capturing every single available data point. (There can be such a thing as too much data.)
If you’re still interested in gathering more than 20 custom data points, you can shoehorn them into GA by using the unlimited custom events!
Reporting is more transparent with Adobe
Adobe is known for making it easy to access all of your data. GA comes with some data gaps. Depending on your site traffic, budget, and data needs, it may make sense for you to get Adobe. Barring that, you can work around by using an API. I recommend using GA to Google Sheets, which pulls each individual data point with no gaps.
Adobe is more straightforward than GA
I have a suspicion that the persistence of this myth may be due to the need for a consultant for Adobe, where GA folks usually fend for themselves. If we’re really getting into ease of use, Adobe has Custom Queries that are more complicated than much of what GA has to offer. GTM (Google Tag Manager) is also much easier to use than Adobe’s approach, which is usually to add Xcode directly to the site.
Adobe wins at boilerplate data collection
Adobe has a bunch of useful default data collection points that make sense for a lot of sites. Dedicated E-commerce event tracking like Add to cart and check out are tracked by default, which is definitely helpful.
GA has essentially rolled out the same sort of tracking, but without much fanfare. Enhanced e-commerce is super-easy to implement via GTM, and it will give you all these metrics and more.