He is so rich, but couldn't afford buying two or more hard wallets to minimize risks of loosing all funds. And why didn't he care about one secure place like a strong-box to keep a copy of the seed-phrase there? I just can't understand being so reckless when it concerns money.
We don't know his story since maybe by the time he bought his coins is the only accessible wallet available for him is the currently one he used, also maybe he just bought it and forget and over the year when bitcoin gain huge price he realize that he have huge volume stored and unfortunately he forgot his password and get a hard time to recover it, this scenario is normal and expect that there are other who are holder from the past will came out and claim the same as this.