Even if that isn't the case, the integrity of the Intercept has been called into question and all would-be whistleblowers would be wise to prefer institutions that have a better record of protecting anonymous sources.

Has Greenwald or the Intercept made an official comment on how they helped the federal government go after a whistleblower?

Do you think it's probable that they exposed Reality Winner intentionally?

She exposed herself with bad OPSEC. NSA was going to find her eventually without the tipoff from the Intercept once they published.

Yes I know that's the case in this instance. I was doing further reading and found a couple other informants/whistleblowers were also burned by the Intercept, and the person who owns and founded it (Pierre Omidyar) has said some very suspicious things about how whistleblowers ought to be treated by the press.