For most, this is probably nothing, but for some, it could be significant.
Instagram recently added a new option which enables you to stop profile visitors from expanding your profile image, which could be a way to limit creepers from peeking on your picture.
As you can see in this image, posted by Yugi Motta on Threads (and shared by Matt Navarra), there's now a new option within your IG profile settings that lets you switch off profile image expansion, which could be another way to protect your privacy in the app.
I mean, most people probably don't care, but if you don't like the idea of people zooming in on your profile image, it could be an extra assurance, while also, as noted, limiting creepers from checking you out in your main profile pic.
But there may also be a practical value here, in limiting impersonation.
Right now, impersonators can steal your profile image, which they likely get a better version of by expanding the picture on screen. By limiting the expanded view, that could make it harder to copy your pic, and while they will still be able to steal a smaller version, it'll be pixelated and crappy, which could be another tell on fake accounts.
Or again, you may just not want people to expand your profile pic.
Instagram added expanded profile images last year, and most people likely don't even know that it's a thing. But maybe you're not a fan, which could make this a valuable, helpful update to customize your IG experience.
Either way, another consideration for your IG presence.