To your point 1: done properly, running isn't particularly harmful to joints and tendons, and some studies even seem to show that running can be beneficial in that regard[1]. The rapid changes in direction that cause the most stress are less prevalent in running than just about any other sport, not even considering the impacts that can occur e.g. in contact sports. Injury rates are not particularly high in running compared to other sports, and even if that were so you should be careful about confusing correlation with causation. A lot of people get injured while running mostly because it's an incredibly popular form of exercise. Do you seriously think there would be fewer injuries e.g. among the same number of people playing rugby?
To your point 3: I know a lot of weight-training addicts like to make that claim, but it's just not true for any reasonable definition of fitness. Running isn't particularly good for weight loss, but weight loss has little to do with fitness. Ditto for weight gain, even in the form of muscle. When it comes to the kind of fitness that actually matters - i.e. developing one's heart and lungs to prevent the chronic problems that kill millions every year - only a few kinds of exercise are better than running. Swimming, rowing, and cross-country skiing come to mind. There are probably a few more, but lifting weights is certainly not on the list.
You personally don't like running? Fine. No exercise is ideal for everyone. But spreading FUD that discourages others from pursuing a healthy habit doesn't seem very constructive.
P.S. Instead of getting your friends to downvote, how about suggesting an actually-healthy alternative?
[1] https://www.sciencedaily.com/releases/2016/12/161209100236.h...