According to the Pwn2Own Toronto 2023 (see link below), Samsung was hacked four times while no team even signed up for Apple or Google..
Honestly, who cares? I mean as far as so what that the S23 was hacked twice the first day. We don't all hang around professional hackers all day and will probably never even come across a single one in our entire lives. This renders the results of this contest as just useless information for us normal people. That's just the first reason this doesn't matter. The major one being, they need physical access to your device to execute any of these zero days they found. They would have to steal your phone, hack the lock method you use's encryption, then they can implement a zero day. The chances of this happening to a regular person is probably about the same odds as winning the lottery. It's not going to happen. So again, who cares? It's just entertainment and also helps the OEM's involved fix major flaws in their products it really doesn't quantify how secure our phone due to reason 1 I gave. The S23 Ultra is perfectly safe and nobody needs to worry. Just stay off the dark web unless you know what you're doing and have proper VPN's and proxies running. Other than that there's absolutely nothing to worry about.
Luckily Pwn2Own discloses exploit information to the vendors like Samsung before they go public. However it does raise an eyebrow on how well Knox is. Realistically, we should be fine as these hackers need to work overtime to find zero-day exploits, but I hope Samsung can learn from these events and work to make their smartphones more secure
Please lay off the Mr. Robot binge watches. The type of exploits and vulnerability you're talking about come from state level actors and teams regularly work to find and patch them, hence regular security updates. No system is 100% secure. If it bugs you that much, switch, but the same situation applies for iOS security.