You want a 2nd HDMI port, probably because you already own HDMI cables by the drawer full. That's a valid something.
However, it's not like you have to replace your monitors because of only one HDMI port. There are cables that go from TB4 to HDMI without dongles. Yes, you would need a new something instead of the something you already have.
Do you really know what the cost of adding a 2nd HDMI port to a system is? I do not. I do know it will be much more than the cost of the actual port connector itself. There's a new hole to be added to the case. There's more robotically soldered points to connect the new port to the system. Of the way the system is laid out on the board, is there enough bandwidth to supply signals to all of the ports? I have no idea the level of complexities involved in deciding what ports are available with the bandwidth of the system, but I do not for a second think that I could do it better.
However, it's not like you have to replace your monitors because of only one HDMI port. There are cables that go from TB4 to HDMI without dongles. Yes, you would need a new something instead of the something you already have.
Do you really know what the cost of adding a 2nd HDMI port to a system is? I do not. I do know it will be much more than the cost of the actual port connector itself. There's a new hole to be added to the case. There's more robotically soldered points to connect the new port to the system. Of the way the system is laid out on the board, is there enough bandwidth to supply signals to all of the ports? I have no idea the level of complexities involved in deciding what ports are available with the bandwidth of the system, but I do not for a second think that I could do it better.