I know that it's definitely not going to be 100% the same (especially since Spanner doesn't even support SQL DML right now), but I think a drop-in replacement into a managed autoscaling database is a really nice alternative to manual sharding.
Right now basically the options are Aurora, Citus, and running CockroachDB yourself.
Right now basically the options are Aurora, Citus, and running CockroachDB yourself.