Importing a fspy scene in blender 3.0 causes tiled rendering

[Romancc]

Hello,
like the title states, importing a fspy scene into blender 3.0 causes it to use old tiled rendering instead of the new and improved progressive rendering engine. Performance is terrible as well.

How to reproduce:

Open blender and try to render a normal engine (result: uses new rendering engine)
import a fspy scene and hit render again (result: old rendering engine is being used with terrible performance: render time of sample scene with 3.0 rendering engine: 10s, after importing 1 min 09s)