but some people said water changes would hurt the plants so I began to wonder.
O_o I have no idea why they would say that...it doesn't even make sense.
plants are perfectly fine with water changes, they are are far less sensitive than fish so as long as your changing your water like you regularly do, there shouldn't be any problems.
your water changes should be based on ammonia tests, unless you know for sure your plants are keeping the water clean, you should do 100% every 3-4 days in a 1.5 gallon.
btw, you can do 100% water changes with plants if they are not the rooting kind. I have a bucket of horn wort sitting outside and I do 100% every single day because dead bugs fall in.
My 2.5 gallon has lots of plants and I test the water every week for ammonia, I get 0.25ppm after about 2 and 1/2 weeks so I do a 50% water change every 2 weeks so its always 0.
If you want hardy plants that use ammonia, hornwort, java moss and guppy grass are good ones. The popular ones like java fern and anubias don't grow very fast or use that much ammonia so they don't make a difference.