It looks like Google is widely showing the landmark icons or pins in the Google Maps desktop and mobile interface now. It is not exactly new, according to Justin OBeirne, Google started to slowly roll this out in nine cities in October 3, 2019 and it is now in at least 80 cities, which is why so many are seeing it now.
For example, if you are in NYC, and you zoom out, for some reason, Google shows the Flatiron Building over the Empire State building, but when you zoom in, you see both.
A bunch of local SEOs are posting screen shots of this in action:
I do hope this is an automated process, I feel sorry for the design team if not! pic.twitter.com/SEhnTG3MgD
— Andy Simpson (@ndyjsimpson) December 9, 2020
Here as well. Amsterdam by Icon pic.twitter.com/YJkjXfHdm6
— Robbert Kleijwegt (@iKleijwegt) December 9, 2020
Me too! pic.twitter.com/TBHD8k0sh5
— Michael Howe-Ely (@MichaelHoweEly) December 9, 2020
Justin OBeirne goes deep into this, it is a very interesting post from him.
Forum discussion at Twitter.