I found this an interesting read:

* read ahead implementation dropped: in the age of SSDs the benefit is not
big enough to have this. All systemd developers have SSDs and no more
spinning disks, nobody could/wanted to support this anymore. The idea was
to read-ahead the bits needed during the boot process and remember it next
time, for faster boots. But with SSDs, this support is dropped.

Linus's approach is "as long as *somebody* is using it, we don't drop
support. Systemd's approach is "we now all have SSD's so we are not going
to bother with this anymore" - not a very mature or inclusive approach. am
I supposed to trust my server fleet to a bunch of dev's that don't really
care about the hardware I am running? I **WISH** all my servers had only
SSD's, unfortunately, they are still too expensive for the amount of data
we manage.

very unprofessional.