Like a privacy based fully open source browser. Wouldnt it be more hackable because every one know the script and is a glopal privacy based gpay alternative possible ? What about targeted hacking is someone using closed source application more better off than someone with ooen source ?
Most of the services you use every day run on Linux servers. Even Microsoft uses Linux on their servers. And these services, not an average laptop, are the main targets of malicious actors.
The vast majority of behind-the-scenes infra that the end user never sees are open-source, even if the end-user part is proprietary. Eg. Facebook and Xwitter are proprietary, but run on open-source infrastructure like Docker, Kubernetes, Nginx etc.
Proprietary OS-s are workstation/office/home PC land. They have way more security issues due to crap coding whereas security problems with open-source server stuff are as a rule the fault of the admins misconfiguring services and not keeping their software up to date.
Linux servers are hacked left and right on a daily basis.