well Russia has a strategic interest in Syria -don't forget Tartus as a warm water port. Much needed.I actually contend that allow Russia to get into the ME, or now Libya, may be a bigger detriment than any gain in influence. What does a world power really have to gain getting bogged down in a quagmire? Let's let them get bogged down, while supporting their proxy enemy like they do to us. It worked well in Afghanistan.
(and they are upgrading to a full dry dock).
With their new land bases in Syria that gives them a quick projection point should they need to team up w/Iran (Qods) or simply go in anywhere.
But mostly they get to influence events in the middle east much easier with a Syrian client state.
Libya is a mess.
Anyone that can get into good graces with any (eventual) government get's a foot in Africa and the Sahel.
Not to mention Libyan sweet crude -easily accessible without any deep drilling