Anything over $20 goes directly into cold storage. Sometimes I change this amount, but it's always a low amount. I'm not risking losing anything more than $100 USD; as such, not really considered closed or open source.
For the wallets I do use, I use only open source wallets. I wouldn't trust anything in Bitcoin that isn't open source TBH. Other software vendors in other industries may be able to get away with it, but with BTC (or other cryptos) the risk is just too real.
As long as it is even an asset, losing it should not even be an option because even if you think the amount it is now is small, in the next couple of years, you would end up finding out what you lost could have amounted into something huge. I guess those who lost their bitcoin when it was less than a dollar would have that to attest to at this stage even with how bitcoin is low today. This is one good reason why for long term holders, it is always very necessary to make sure you are using a wallet where you have full access to your assets and cannot easily get exposed to vulnerabilities.