> I just wanted to upload photos.

You can absolutely still do this. I'm still a Flickr Pro subscriber since 2015, and I still regularly upload photos to Flickr. I don't think there was a set of changes that reduced Flickr to an also-ran, the entire market shifted. First, there was a shift away from photography being focused on what I will short hand as "quality" towards being focused on what I'll short hand as "moments" with services like Instagram, which had 100m users by the end of 2013 and continued growing exponentially from there, which was deeply interconnected with the introduction of reliable fairly high-quality phone cameras built into smart phones.

Flickr was, and continues to be, a place where people who use actual camera equipment post photos that are taken not just to capture a moment, but to express a scene, using technique and artistry to do so. That type of high quality photography doesn't really get much traction in more contemporary social media, because the photos of moments shared on Instagram weren't about the photo, they were about the moment. It was about proving that you were in a place or experienced a thing, and the place or thing giving you social value. "Pics or it didn't happen."

Instagram has now largely been supplanted by TikTok, because short video is now much more of a common, engaging, and desired format than photography, and thankfully this means Flickr in 2026 is once again a refuge of die-hard photographers sharing their works, and not seeing much attempt to change it into Instagram 2.0. Many (maybe most) of the photos on Flickr are now taken with smartphones, but there is still an expectation from the community to focus on expressing a scene using technique and artistry, and modern smartphones now have good enough cameras to do just that without detracting from what you're trying to express.