Ed Sheeran collaborates with Producer/Songwriters, those like Bruno Mars, whom many pop artists have collaborated with and who has many hits most don't know he produced or help write.
Some actually collaborate with Producers/Songwriters chosen by the label because the label wants a certain sound. So they collaborate to make that Ed Sheeran written song, into the modern pop hit.
Labels work with the artists to create a certain song or sound they want, like WAP and Old Town Road. Which is a trend I have been noticing, country rap.
There is nothing wrong with collaboration as most all singers do collaborate with musicians. Janis Joplin did this, the old Motown and Lounge Jazz relied on the collaboration of the musicians.
It's when the label decides to choose whom to hire to work with the artist for the collaboration because they want that certain style of song that sells and they can market on commercials, in the stores, during sports games, halftime shows, charity events, and the many other ways we get bombarded by the marketing of these songs.
That has an effect on how people listen to music as repetitive listens will make people enjoy the music. We all do that here, by giving an album/song/band more chances to like a certain song/album/bad.
In other words, those collaborations serve no purpose but to sell and market a product to the masses, so the people can buy the products in the commercials, go to the sporting events, and even do a global dance routine to. It's a way of using sound manipulation to convince people to buy. As people hear a famous song and turn their attention to wherever that song plays from.