I told somebody I know who knew about Reddit's API changes about Lemmy. He has a master's degree in Computer Science and works as a software engineer. But then, he told me that it's too confusing to get into, even for someone like him. This is great feedback and I hope that these issues will be fixed in the coming months.
Lemmy is still in active development and there are some missing features, but it is very usable. Your friends' complaints, some are a bit exaggerated and some are really not that big of issues that will get resolved eventually.