This profile song feature used to be a highlight of the MySpace platform, where users could select multiple songs to play on their profile whenever someone visited it. It was meant to be a showcase of the person's personality, and users were pretty picky about which songs they would use to set the theme for their profile.
Eventually, with the death of MySpace, this feature was also lost to a lot of users who still miss the ability to use music to express their emotions to their audience. However, Instagram won't be the first platform to try and revive it, as a dating app called Raya also lets users add songs to their profiles so that dating matches can experience their personality through this added dimension.
The fact that Instagram is testing this feature also marks a key change for the platform, as it would mean that they are also working on integrating music into the app, just like TikTok. So, chances are that soon enough, users will be able to add music to not just their profiles but posts as well.
While this is a must-have feature to look forward to, we still don't know how long it will take before the company makes it public, as they are pretty adamant that this is still in internal testing only. Still, the nostalgia of being able to set a profile song once again is enough for most users to continue being hyped up for it.