On a serious note, Neon is Postgres and Planetscale is MySQL. Neon has 100% compat with Postgres and Planetscale supports most but not all MySQL. Neon has unlimited storage a single node compute. Planetscale is scale out architecture on top of Vitess.
Neon scales to 0 and more cost effective b/c the architecture.
Much much better :)
On a serious note, Neon is Postgres and Planetscale is MySQL. Neon has 100% compat with Postgres and Planetscale supports most but not all MySQL. Neon has unlimited storage a single node compute. Planetscale is scale out architecture on top of Vitess.
Neon scales to 0 and more cost effective b/c the architecture.