It's not clear what requires immediate re-learning with systemd unless the administrator has a habit of directly altering rc.d symlinks, which hasn't been a best practice for a long time.
Existing init scripts work, unaltered, with systemd. Enabling and disabling services with chkconfig maps transparently to the proper operation in systemd. Mounts configured in fstab come over, automatically, as mount units and can continue to be managed the same way as before.
None of those compatibility features is going away any time soon.
And, for admins wanting to transition to the native tools, extensive documentation and guides  exist.
If that's not good enough for you and you can't appreciate the value these tools provide to others, I can only describe your attitude toward keeping SysV init as selfish. The FOSS world doesn't owe you stagnation once it's met your needs.
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