No company invests billions into industry projects with that kind of political uncertainty. You can see it in the numbers: BASF stopped basically all investments in Germany. You cannot bet your whole company on a tax cut that was recently introduced and is already scheduled to disappear.
Managers bet their companies on more stupid stuff all the time. Elon Musk just bet SpaceX and Twitter on datacenters in space …
In the political reality of Germany there is literally 0 chance that these tax cuts won’t be extended. Low investment by BASF has many reasons, but their inability to get politicians to extend that tax cut isn’t one of them.