If there is no difference on the syntactic level between owning and non-owning pointers, like in Go programming language, like in Python, then I agree with you

If there is no difference on the syntactic level between owning and non-owning pointers, like in Go programming language, like in Python, then I agree with you - it's extremely easy to make a cycle. But if there's a difference between owning and non-owning pointer, then backlink to parent object in child object could be non-owning and other issues could handled in similar manner. Cycle detector which stops the program with references to the source code where the cycle was created - is a good idea, because in server systems under heavy load it just could be disabled. Basically it's a debugging tool, once it was proven by the testing that there are no bugs, these checks can be turned off in production. Like a C assertion checks.