Usually reduced significantly compared to the standard 5.4GB. Minimum System Requirements

Because Windows Update is usually disabled or broken, you will miss critical patches. The 21H1 build you are installing reached . That means any vulnerabilities discovered after June 2023 (including major ones in 2024/2025/2026) will never be patched.

Can’t install a feature update? Need a driver that requires a missing component? Microsoft support won’t help. Neither will the modder, who’s likely anonymous.