Mixed reputation for providing a safety guarantee but are hard to achieve, slow, and sometimes promise more than they can deliver.
Heterogenous distributed transactions which enable Atomic Commits across participants using different technologies is quite challenging. Transactions using the same technology and running the same database software is much easier.
This is the classic way of keeping data systems consistent which uses 2PC. These systems provide Linearity which implies guarantees that you can read your own writes (which is a very useful guarantee).