I just read a really interesting article regarding this. Turns out that Google is basically using the new features in iOS 14 to really push (force) iPhone users to download the Chrome app. The features being: A new home screen widget available for Chrome that Google refers to as the “quick search widget”. The other feature being the ability to now choose between Safari and Chrome applications to be the default app for internet. Not just the default website, the default APP. This option is also now available for the Gmail app. So basically, if you set Chrome as your default browser when you open a link from another app, it will open in Chrome. Similarly, if you set Gmail as your default email app, any time you tap on an email icon on the web, it will open the Gmail app. So now we know the “why” behind this annoying problem, we just need to know how to fix it. Also I believe the reason ad blocking apps aren’t working for this banner is because it’s not technically an ad or even a pop up, but rather written into the website. I’m just glad I’m not the only one annoyed with this.
New Default Browser App setting:

New Google quick search widget:
