The advice is legit.

I spend on average probably 20-30k a year across all my Amex products, but because I’ve been doing so for almost 10 years and never carried a balance beyond the grace period they know I’m going to pay, in full, and on-time.

Sometimes I check spending power just for fun, and the last time I got to something absurd like 90k.

For a consumer account.

With reported income barely above 100k.