I'd come to the realisation a while ago that, deliberate or otherwise, limiting website usability or accessability to recent / high-performance kit is quite possibly an effective market-segementation tool in a space in which physical location (e.g., an up-market high-street address) is not a viable differentiator.

See: https://news.ycombinator.com/item?id=27410503

I'm not a fan of this, mind. Just aware that it's a possibility. And you're giving voice to that as a deliberate choice.