When placing a command block with the auto tag that has a command to set a spawner with a specific entity in, the spawner will instead be a default pig spawner.

Steps to reproduce:

1. Use this command to get a command block with a command to /setblock a spawner with an armour stand that is automatically run when it is placed.

   /give @p command_block{BlockEntityTag:{Command:"/setblock ~ ~ ~ spawner{SpawnCount:0,SpawnRange:0,MaxNearbyEntities:0,RequiredPlayerRange:0,SpawnData:{entity:{id:\"minecraft:armor_stand\",ArmorItems:[{},{},{},{id:\"minecraft:stone\",Count:1b}]}}} replace",auto:1b}} 1
   

1. Now place the command block you were given and notice it will place a spawner with a spinning pig.
2. Expected result (do the same steps above in 1.18): Placing the command block will place a spawner that has an armour stand with stone on its head.

Note:

Spawners show correctly after a relog