No, it hasn't forgotten anything. I'm afraid you've fallen into this weird anti-Mando 3 echo chamber. I don't know exactly what accounts for this bizarre internet-wide anti-Mandalorian reaction just now among relatively few people, but most hardcore old Star Wars fans I know, as well as people new to the franchise via Mando, were literally cheering throughout season 3, and the finale was extremely satisfying and meaningful. It's no different at all than each of the other seasons, and represents a very natural weave of all the plot threads introduced so far.
The writers did a great job. That iconic ending shot of season 3 was perfect, like any great western. There are no reasonable grounds for complaint. It's a serial with a beginning, middle, and end.