The idea of removing (or suspending) cards once they reach a certain interval is harmful, especially if the interval is relatively short. Once you delete a card, you can't be sure that you will be able retrieve the information when you need it.
I would speculate that this idea was born in an attempt to lower the review load caused by using sentence cards. Sentence cards take longer to review compared to other card types. In order to lower review load people suspend older cards and only spend time on relatively young cards.
Instead of sentence cards I recommend using targeted sentence cards because they allow you to take shortcuts and review faster.
It's alright to suspend or delete cards once they reach obscene intervals like 10-15 years.
To find such cards, you can open the Anki Browser and type
3650 corresponds to card's interval in days.
For more details see Card retirement.
Several Anki add-ons have been created to retire old cards automatically. They interfere with Anki's scheduler and have been reported corrupting users' Anki profiles.