Good combination for Budget Wildlife photography.

I would like to upgrade my equipment. Will the following be a good combination for wildlife photography on a budget ?

Nikon D7200
Sigma 150-600mm f/5-6.3 DG OS HSM Contemporary lens

I shoot mostly in low-medium light conditions with dense vegetation.

The Sigma 150-600 has a good range. However, the f6.3 wide aperture is not great for lowlight. Nevertheless with high ISOs these days, one can use it. I would say for beginners it is fine.

PS: Though I use Canon, when asked for a suggestion, I am equally open for Canon as well as Nikon. However, I would like to point out that not all is well with Nikon these days. It no longer remains a powerhouse as it was earlier. It has to depend on Sony for its sensors and innovation has slowed. It is no longer the leader it used to be. So anyone getting into this system for professional use need to be careful. However, I hope that my words as well as similar words by Nikon watchers be way off the mark as we want more competition in the area.