Doing good financial management is the first thing to do before investing in Bitcoin. It's true what you said, not to be aggressive at the beginning of investing, and it's better for us to have more knowledge about Bitcoin before starting to invest.

Many beginners just follow what's popular in the market or what's talked about more. But I have a friend who moved some of his money from selling a property business to Bitcoin. That happened a few years ago. I don't know how long and how far he analyzed the potential of Bitcoin, because previously I knew he was not interested in Bitcoin and crypto. He told me about his transfer, he liked the property business, and then set aside his money to own Bitcoin. And I'm sure people who usually do business like that won't come in with small funds.
I haven't met my friend again, but I'm sure he sold his Bitcoin, at least some after Bitcoin reached its last ATH.