Sorry to hear you’ve had difficult experiences too. It’s quite odd, as I’ve been working professionally in freelance writing for years, and not until I joined Medium, did I get some frankly, quite insulting feedback. The worst was for an article that a magazine had previously paid £225 for. There was nothing wrong with it, but the editor didn’t like the style — because a lot of it was written in passive voice (and her bit of software said this was bad). I pampered to her demands, but wish I hadn’t as reworking it took ages and it didn’t get a lot of reads.