Have you actually tried to connect more than one device to the hotspot? Maybe they took the setting away because they took the limit away? I would think hotspot is controlled by your carrier, and these days it's how much hotspot data they allow, not how many devices.
To connect to your hotspot, one needs to know your hotspot password and the hotspot needs to be on, so it's likely there is no need to limit connections since you, presumably, do not share the password with everyone.
If you enabled auto hotspot through family share, you likely would have the ability to limit connections from there.
