locking a server to one option only

Is it possible to lock your server to direct play only so that users can not over tax it by choosing transcode ?

for those “plex ninjas” out there using the advanced settings if one limits “Maximum simultaneous video transcode” that limits inbound or outbound? In other words if I set this to 1 does this limit only 1 user from using the transcode option or does it limit my server to only transcoding 1 stream at a time? I read the guide but this is not as clear as it should be