Unexpected error behaviour: Parameterized generics cannot be used with class or instance checks

`mypy` reports success for
```python 
import numpy as np
x = "a"
assert isinstance(x, np.float64)
```
but fails for
```python
from numpy import float64
x = "a"
assert isinstance(x, float64)

```
with the error `fails.py:3: error: Parameterized generics cannot be used with class or instance checks`

I'm using `mypy` (0.931) and `numpy` (1.22.2).

Why do I get different results?