「彼ももうちょっとがんばればよかったのに..、みたいな…。」
or
「なんか、お腹減った、みたいな…」
Just for some examples. Is it some sort of filler? I understand normal uses of みたい but I don’t understand what it means at the end of a sentence.
Maybe you've heard expressions like みたいな気がする and みたいな感じがする.
みたいな is just a shorter form of that. They all mean something along the lines of
Japanese use this expression to make the sentence softer/more careful/less sure, as to not present it as a fact, but just your humble opinion/feelings.