This question is old, but I thought I'd add my opinion as I feel there's a bit of contextual consideration lacking from the given answers.
There used to be a lot of consideration given to the overall length of urls because of how they were displayed in the SERPs. The thought was, that removing stop words was a good default practice because it would help address situations where longer URLs would be trimmed in display. This would increase the liklihood of a url such as /the-single-most-influential-keynote-speeches-of-any-of-the-most-popular-colleges-in-the-world/
of appearing for keywords like most influential college keynote speeches
. When stops words were removed, longer urls had a higher chance of having core keywords displayed in the SERPs. Today, Google seems to dynamically-display different segments of urls depending on their relevancy to user searches, such as the above url might appear as follows:
https://www.example.com/...colleges-in-the-world/
That's really the only 'direct impact' consideration that I regard to be of concern—and it's not of concern anymore for all practical purposes.
I think that it's good practice to manually remove some stop words sometimes, because urls often need to be practically usable for users to remember/write down/etc. That's more UX than SEO though.
All other considerations for the removal of stop words are, IMO, purely subjective to use cases. For example, gigantic sites like StackOverflow likely need to keep stops in urls because different questions (legit different) might only be differentiated by nuances of stop word usage. A small coder's blog however, likely having a single post per topic such as this, would likely be better served to create as short of a url as possible since there'd be no duplication issues.
For a full range of url considerations I'd suggest reading the following article:
https://moz.com/blog/15-seo-best-practices-for-structuring-urls
TL;DR: There's not much technical justification for the removal of stop words from post urls anymore, and such consideration is highly subjective to use-case and personal preference.