In 2011, if someone said they had 5 Bitcoin, they had 40 cents.
In 2017, that was worth about $100k.
6 years difference and a whole different perception of value. Where will be in 6 years? Do you know?

Disclosing what you hold today may not be a big deal, "a regular wealthy person" as you say. But a year from now, 3 years from now, your comments still exist in a crypto forum and you're publicly worth at least $5m in a currency that is largely stored with access available in your home.

OPSEC isn't just about today, it's about many tomorrows.
A regular wealthy person holds their wealth in investments not easily liquid.
A $10 million net worth is likely a $1m home, a few million dollars in stocks, a few million in other investments, and maybe a few hundred thousand accessible max, even with a gun to your head.
A $10 million net worth in crypto is likely mostly liquid enough to all be accessed with a gun to your head.

It's a far different ball game when you're your own bank. As risk increases there are steps you can take. Not disclosing what the bank holds and not disclosing where the bank is are two of the most basic methods to not end up with a gun against your head.

https://cointelegraph.com/news/uk-cryptocurrency-trader-robbed-at-gunpoint-amount-stolen-unknown