Encrypt your PC's disk without giving the keys to Microsoft

Is VeraCrypt still viable alternative? Are there any viable alternatives?

VeraCrypt has been tried and tested but it appears to perform poorly on modern NVME devices due to inherent limitations in its TrueCrypt based architecture. As a Windows FOSS alternative, you can consider DiskCryptor. However, unlike VeraCrypt, it has not been audited (to my knowledge) and lacks many QoL features. Use at your own discretion.

It is being maintained here: https://github.com/DiskCryptor/DiskCryptor

Is the described method good for Enterprise and IoT Windows versions?

> The actual encryption technology hasn’t changed at all—all we’ve done is change where the recovery key is saved.

So the same shit. The only difference is that besides Microsoft, you also have the key.