This is just wrong info. Search HN comments from ‘craigkerstiens, an early employee. Significant innovative product development continued for a few years after the acquisition.
That's always the case which is why I said "about the last time" instead of "the last time". There is always stuff in the pipeline, there are always still people who care for a while but they see the writing on the wall just like the rest of us, they leave, and it becomes a self-fulfilling prophecy. I'm not saying there aren't/weren't good developers/managers at Heroku, I'm saying the sale to Salesforce started the end for Heroku.
If the security incident a few months ago wasn't a clear "we don't care about Heroku" then I don't know what will wake some people up.
A quick Google of this dude's handle/name and the first link is his blog with a reflective article about his experience at and subsequent departure from Heroku:
