You're not giving them enough credit. Pun not intended. They paid down high interest accounts with the spare cash hence the evidence I saw, fico score increase

You're not giving them enough credit. Pun not intended. They paid down high interest accounts with the spare cash hence the evidence I saw, fico score increase across the board. If they had just been taking on more debt with the same income, fico scores would decrease. It's essentially a ml model for predicting the risk of default.