Centos 9.4 /x86-64:
GRUB2 2.06 usually does not display (to VGA) boot menus during the boot process, but sometimes it does. Full booting is successful, but no menu is usually displayed.

Contents of the /etc/default/grub file:

GRUB_TIMEOUT=10
GRUB_TIMEOUT_STYLE=menu
GRUB_GFXPAYLOAD=text
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT="console"
GRUB_CMDLINE_LINUX="resume=UUID=c44cc38f-91ec-49a8-91bc-4e76b121e6cd"
GRUB_DISABLE_RECOVERY="true"
GRUB_ENABLE_BLSCFG=true

Of course, grub2-mkconfig was run successfully.

There were no error messages in /var/log/boot.log .

On CentOS 7 on the same hardware GRUB2 worked fine.

Settings:
GRUB_TERMINAL_OUTPUT="vga_text"

or exact value for:
GRUB_GFXMODE

don't helps.

It seems like there are some problems with other timeouts.