Can someone rip your work? Yes. Is that really an issue? No. Just stealing the code changes nothing, the person needs to invest money to continue build it themselves. The original developers will always be at an advantage since they know the code base. The fork (the new version) also won’t benefit from any of the changes by the original developers, or they need to carefully copy them over. If the hostile fork is also open source then it doesn’t matter since you can just take their changes if they are good. Making it mutual.

You can also use licenses that forbid the closing of the source. Doesn’t stop real thief’s, but it gives you a tool to stop it and also anyone who ignores a license like that is also generally not very competent.