According to your logic all FTP will have level 1 golem and level 8 witch. Any sane player will realize within few weeks of playing that golem is a better epic than witch.
When did you start playing CR? Golem wasn't very popular at first. The Golem meta became strong at a time when one could have easily gotten Witch to 3-4 lvl already.
Level 3/4 Witch is only a few weeks lost requesting in the grand scheme of things.
Not much of a dent when you talk about getting to lvl 8.
When you are there at that time, you don't see "the grand scheme of things" that we can see now looking years back. You are in a game of a few months. And you are invested many weeks into a card. So instead of investing many more weeks into a new card, you keep at it. Games nowadays raise to fame and disappear way too often, to be expecting to focus on a long term plan that loses your months of progress in order to get - possible - gains in a year or two. In a year or two CR might not have existed anymore for all that player knew, or the meta could have shifted and Golem nerfed. It's so easy to look back and give wise advises post factum.