I have a different advice for aspiring mathematicians. Learn in the way you want. If you enjoy learning the prerequisites or feel like you need to, by all means

I have a different advice for aspiring mathematicians. Learn in the way you want. If you enjoy learning the prerequisites or feel like you need to, by all means learn it carefully. There are enough mathematicians on either side of this advice and indeed of most advice. Don't take other people's opinions too seriously. Other people only know what worked or didn't for themselves, they have no idea what will work for you.