Just because a competitor does a certain feature or something a certain way doesn't mean they iterated quickly, perfected it and you should copy. It could also be that they simply have enough customers they are scared to change anything for even the better and are stuck. At my last company we got to a point where the executives were happy making zero product changes to make life easier on our support team and not make customers mad due to re-training and causing new bugs.
Some others may be nimble enough to add whatever your killer feature is. But their management team or investors may want to keep with what works and not vary from that path.
Point is some companies are in different points of their life cycle. I think it is good to know who the players are but to use your own product vision to guide you. If you have no product vision and your goal is to just copy, well good luck with that. Why a product is built a certain way isn't something you can always figure out.
Some others may be nimble enough to add whatever your killer feature is. But their management team or investors may want to keep with what works and not vary from that path.
Point is some companies are in different points of their life cycle. I think it is good to know who the players are but to use your own product vision to guide you. If you have no product vision and your goal is to just copy, well good luck with that. Why a product is built a certain way isn't something you can always figure out.