To clarify, reentrant errors are not atomicity errors. Fully serializable transactions can have reentrant errors and they often do, but that class of error is a case of the code not doing what you expect rather than an atomic violation.

What I would instead wager is that it's too easy to introduce reentrant errors in Solidity.

I've noticed since the DAO exploit, the ecosystem has been better about this though. For example, Solidity's docs has a section of reentrancy, and even the in-browser editor can warn you about reentrancy in some cases. Seems to be improving, though unfortunately after big expense.