The concepts behind are the hard thing. If you can't figure out the concept, the notation doesn't make much sense - and it is the notation that you meet first, so it seems to be the culprit.
Which is not to say that all notation is equally good - some is exceptionally bad, and other just confusing. The article mentions [x] which was i use for almost 200 years despite being confusing - but was then fixed into something non-confusing.
Similarly, for most uses, Leibniz's differential notation (dy/dx) is superior to Newton's (y with a dot on top) - and is now universally used in those uses - but for a long time Newton's dominated, mostly for political reasons (yes, over 250 years later).
But these are the exceptions: Usually, like in the floor/ceil case, when a better notation comes along, it is quicky (30-40 years...) adopted.