It isn’t if we’re talking about histories of science and medicine written between, say, 1850 and 1950. Nowadays I agree, few would argue this directly. But then again, that’s because of Butterfield and the turn away from Whig histories among hist sci types - which, itself, was far from inevitable. And if you read Weinberg, I think you do still see that point of view in play.
The quoted proposition is really two rolled into one:
1. Progress is inevitable.
2. Conditional on progress occurring at all, it has to take something reasonably close to a specific path.
The first view seems to be quite widely held. I think it's false, but the second one is true. Is the version being critiqued here, the first one, second, or both?
It's also one of those typical philospher's tricks: you can get a scientist on record agreeing that such-and-such is reasonable, but they're thinking about something like "maybe the Hall effect could have been discovered before or after the completion of Maxwell's equations," while every reader is imagining natural science but based on drum beats.