First, they are not familiar with the rules of the forum. You can read the link below.
Reading the rules of the forum is encouraged, but one does not need the forum rules to decide that plagiarism is wrong, it's frowned upon in writing and most people who do it, have a bad intent.
You can quote other people's information and indicate the source. But you must have your own independent opinion expression.
Not necessarily. Putting a link to the source would indemnify the user from any penalty, it is however suggested to have your own opinion and not just regurgitate other people's content.
Second, novices do not have a strong reserve of knowledge, so they cannot form their own opinions, and there is nothing to say. They must improve their cognitive level through a lot of reading.
Anyone can form an opinion, it does not have to be a correct one, that's the reason the community exists; to assist users in understanding more about Bitcoin. Read, understand, inquire, read some more and repeat.
+1 for the the link to the forum rules, also, following posts of most merited users would provide useful content, but I do not think users need to follow the most merited posts as they may not be informative, be in a different language, or not be of interest or a newbie. Users should find topics they are interested in and research more on those.
