The actual thesis of point 2 is about plagiarism, and the thesis would remain the same if the sentence you quoted were removed completely. Your portrayal of it moves the out-of-context snippet to the forefont of the argument and makes it sound like an issue of "tradition for tradition's sake" or something similarly indefensible, but you refuse to engage with the real argument being made, hence why I suspect you are acting in bad faith. Are you suggesting that not attributing credit to work you've copied from is the way things should be going forward? If you are, then argue that point and make it earnestly. Instead you continue to avoid any substantial discussion of the points raised and only went for a cheap "gotcha".
I do not agree that the thesis of point 2 is about plagiarism.
Plagiarism is a minor concern in research papers. Plagiarism means that the paper has 0% new content and everything in it is extracted from older works and combined.
However, even very valuable research papers may have only 1 new idea or only a few new ideas, which can be applied only together with a much greater amount of old knowledge, which might be mentioned explicitly in the paper, with proper attribution, enabling the reader to search the original sources, or the necessary old knowledge may be implicit, the writers assuming it to be known by the readers.
It is important that the writers should not imply that some old idea is new, by omitting to attribute it, but much more important is that when they mention some ideas as being old, they must also provide sufficient information about the sources of those old ideas, so that the readers will be able to access them.