The new slight upwards knockback when performing a smash attack added in 24w13a makes it possible to output a massive number of smash attacks by spam clicking. This is because you can do an infinite number of smash attacks as long as you do not touch the ground. Part of the problem here is also that you can do smash attacks against entities during their invulnerability timer.

In combination with MC-269765, you can repeatedly spam a large fall damage increase by spam clicking (see second and third attachments). Also relates to MC-269947.