The problem here is the graphics drivers; on your system they're taking longer to load than it takes to check and mount the filesystem - so there's no reason to start the splash screen, since we can already start X.
On HDD-based systems this is worse because we do the ureadahead phase before loading drivers; thus it can take a long time for a splash to appear.
One "solution" is to use the initramfs and start plymouth as a critical step:
The problem here is the graphics drivers; on your system they're taking longer to load than it takes to check and mount the filesystem - so there's no reason to start the splash screen, since we can already start X.
On HDD-based systems this is worse because we do the ureadahead phase before loading drivers; thus it can take a long time for a splash to appear.
One "solution" is to use the initramfs and start plymouth as a critical step:
echo FRAMEBUFFER=y > /etc/initramfs- tools/conf. d/splash
update-initramfs -u
But that introduces a significant delay into boot just to get the splash screen up for the rest of it