I read here that those black spots caused by either bacteria of fungus aren't bad for my Majesty/Areca palm, but are they bad for other flowers which will be next to the palm? Will they become contaminated and have issues? I have basil, mint, aloe vera, bamboo, rose and some other plants on the bottom racks underneath the Majesty/Areca palm. Would it be better to keep the palm on the bottom rack instead or completely separated from other flowers? Thanks a lot!
The bacteria/fungus/virus is not contagious. Possibly, if you had another palm tree and you transferred some soil to it you could transfer the problem.
All the other plants you have should be fine