Google made the same decision as Apple when they removed Fortnite in response to Epic Games completely bypassing the store's in-app purchasing flow, thus losing their 30% revenue cut, so the motivation is likely not 'to make Apple look bad'.
This is probably just a good show of faith to regulators while Google still collects their percentage of subscription revenue from Spotify on the backend.
> percentage of subscription revenue from Spotify on the backend
This is an advantage of Google vs Apple. Google has multiple business relationships with Spotify. An increase in advertising dollars, infrastructure spend on GCP, etc could all offset the lost revenue for Google here.
This is probably just a good show of faith to regulators while Google still collects their percentage of subscription revenue from Spotify on the backend.