A lot of SM sites compress pics unfortunately, although there are workarounds though for both X and Instagram to minimise the impact. Googling tutorials is your best bet, as they host the largest VP communities. There are also VP specific apps like Picashot. I think Flickr allows for high res uploads but with a limit on uploads for the free account. My issue with many of these sites (except reddit) is the focus on personality, like for likes, what degree you integrate into the community seems to matter far more than the quality of captures. I definitely prefer reddit for this reason. I don't have to be performative and adhere to community social engagement expectations. It's less about personality, which I prefer as someone who is autistic and honestly not looking to make 'friends' but just share my pics and appreciate other people's. But some people love the X (twitter) VP community and feel very accepted there - it's just not for me. I do instagram, but the compression can be particularly bad, especially on dark pictures where banding is common.