Skulk blocks should drop experience orbs when they explode. This is not currently the case on Java edition, but is essential for the intended use case of skulk blocks, which is AFK mob farms.
Requiring player interaction to drop the xp totally defeats the purpose of turning the xp into skulk blocks in the first place, since if the player had to be breaking blocks they may as well just be hitting mobs.
Given the only way to currently get xp without player interaction is with zombie piglins, and that is intended to be removed from the game at some point, this is an absolutely necessary change.
I don't envision this having any balancing issues given I'm fairly certain this is already the case in Bedrock experimental, and the skulk blocks only containing xp orbs with 1 xp each already limits the speed of any xp farm utilizing skulk blocks since the player can only absorb 1 xp orb at a time.