bug#57466: 29.0.50; *Messages* buffer stops following after `kill-buffer'

[laslydone]

  What happened:
When you `kill-buffer' on *Messages*, after it remakes itself point no
longer follows output.

  To reproduce:
$ emacs -Q
C-x b
*Messages* <RET>
C-x 2
C-x b
test <RET>
C-x k
*Messages* <RET>
C-x b
*Messages* <RET>
C-x o
; You should now be back in the test buffer
C-n C-p C-n C-p
; Run ^this till the last line in *Messages* is off screen.
; It no longer follows output.