While 'sed -E' and 'grep -E' support the extended regular expressions (ERE), which is the RE syntax of awk, any reasons why we stick to the basic regular expressions (BRE)? Firstly, 'buy 1 get 3' is appealing because the ERE syntax works in these commands, reducing the cognitive load when learning and using. Secondly, regarding the portability, I do not have a clue about the targeted operating system or whether we will log in to an ancient machine. Since in Ubuntu 23.04, those commands support the ERE, I think it should run well on other UNIX-like systems having software updated. Thirdly, the BRE is a little counter-intuitive. For example, some meta characters like '?', and '+' have to be backslashed to become quantifiers, but '*' does not have to. Someone who has not read the manual may fall into this pitfall, not understanding what goes wrong.