Large brokers like Fidelity typically offer stronger safeguards and regulatory protections. In extreme scenarios, if there were systemic risk concerns, major institutions are also more likely to receive government support — similar to what happened in cases like SVB to prevent broader contagion.
TL;DR: Avoid putting your money into small, questionable, or uninsured brokers.
Crypto is significantly riskier than traditional stocks, yet many people still choose to buy and hold through major exchanges. Likewise, the probability of bankruptcy for an individual speculative company is much higher than that of a large, established broker — yet investors continue to trade speculative stocks. Ultimately, it comes down to understanding risk versus reward. There's no need to overcomplicate it.