Yeah, once you dig into economics, technology and science of the era it often feels like the big discoveries were inevitable. That doesn't make these people any less great, it's just to say there are many more great thinkers that people are forgetting about.

But I'd like more explanation as to why Maxwell or Newton are any less replaceable: all 4 of "Maxwell's equations" have other names attached to them (the exception is Ampere-Maxwell law [1] which Maxwell contributed an important term to), and Newton had a number of contemporaries who were making similar discoveries but are often forgotten.

[1]: https://en.wikipedia.org/wiki/Amp%C3%A8re's_circuital_law