It's not possible to update score values on signs like when you're monitoring something, because now it just crash the internal server (memory and CPU goes all way up and a lot of lag comes with it)

Steps to reproduce:

• Create a scoreboard like: /scoreboard objectives add example dummy
• Put a sign somewhere
• Give yourself a command block: /give @p minecraft:command_block 1
• Place it somewhere and set the command /data merge block <sign coords> {Text1:"{\"score\":{\"objective\":\"example\",\"name\":\"@p\"}}"}
• Set a score value to yourself (just to show something): /scoreboard players set @p example 10
• Change the command block to a repeating always active one to update the sign every tick

Expected result:
A sign with my score value printed and always up to date.

Actual Result:
Both CPU and memory gonna get high values and then in most cases it will stop working because of a kind of "out of memory" thing (probably the issue). It won't crash, but it will be unplayable (< 1 FPS on an usual > 400 FPS computer). My Minecraft with -Xmx12G got almost 14GB used RAM in 5 seconds after loading the map, and it was unplayable since the beginning of the loading screen.