1. Transactions are not implemented in most of the "eccentric" solutions
2. SQL solutions are more battle tested.
3. The relational model fits most solutions quite well
Where the relational model doesn't fit or transactions are not required, then it may be worth looking at other solutions.
Polyglot persistence is also another moving part too, it needs time, expertise and infrastructure to deal with, so even if a non relational model makes sense and there is currently no need for transactions. Who knows when transactions would be a good idea?
1. Transactions are not implemented in most of the "eccentric" solutions
2. SQL solutions are more battle tested.
3. The relational model fits most solutions quite well
Where the relational model doesn't fit or transactions are not required, then it may be worth looking at other solutions.
Polyglot persistence is also another moving part too, it needs time, expertise and infrastructure to deal with, so even if a non relational model makes sense and there is currently no need for transactions. Who knows when transactions would be a good idea?