Well, that's one way to make the only remaining feature of your product sound like a bad thing...
I've been a pro user for awhile. I guess the downside of this is that I now feel locked in, having well over 1,000 photos. I think previously, had I downgraded to the free version, I'd be able to keep all my photos but no longer provide them as full-size downloads. I don't have a particular complaint with Flickr as a service, it's just I don't do a lot of photography other than casual uploading to Instagram these days. That said, that Smugmug is committed to taking a different, coherent direction provides me with a lot more confidence than the years of Yahoo doing virtually nothing.
edit: maybe I'm grandfathered in for unlimited photos, if I were to downgrade to Free? The wording in the announcement is unclear.
1000 photos can go a long way if used in the way Flickr was originally intended, which as you noted was a portfolio of sorts.
That's not how I'm reading it. It seems like it'll affect all Flickr users across the board.
I mean, that's what they want it to be now, but I don't feel like that's what it was under Yahoo...