Case class deserialization doesn't go through apply in Scala 3

[smarter]

https://com-lihaoyi.github.io/upickle/#Basics says:

Case classes are serialized using the apply and unapply methods on their companion objects.

This isn't the case in Scala 3:

case class Foo(x: Int) derives ReadWriter
object Foo:
  def apply(x: Int): Foo =
    assert(x > 0)
    new Foo(x)
@main def Test =
  read[Foo]("""{"x":-1}""") // Successfully constructs a Foo.

This is because deserialization uses Mirror#fromProduct which just calls the constructor:

upickle/upickle/implicits/src-3/upickle/implicits/Readers.scala

Line 72 in 6e551ac

override def fromProduct(p: Product): T = m.fromProduct(p)