The reason people stay in Lunar is simply because casting two Wraths is faster than casting two Starfires, and the gain of being in Solar for the Wraths you cast in that non-CA/Incarn window isn’t worth the extra cast time on the casts of Starfire. We have a lot of things in our talent tree (along with our outrageously strong 4pc) which incentivizes maximizing entering an Eclipse (any of them: Lunar/Solar/CA/Incarn). You get a free spender that hits harder every time you successfully enter one, so it is all about doing that as often as you can.
Empowered Wrath is still definitely better in ST, which is why you use it in CA/Incarn, and why you enter Solar using Warrior of Elune if you happen to be talented into it, as you can be on-the-move as you enter your next Eclipse phase and not have to wait 4 years for those two Starfires to finish casting.
As for 10,1, even though they’re gutting our 10.0 4pc on day 1 of the patch, I suspect entering Solar will still be niche like it is now. IMO this is a “be careful what you wish for” situation, as I loathe casting two SFs to enter Solar, so I’m fine with this weird degenerate play. As others have said in this thread, it probably is time to retire Eclipse’s mechanic how it is now and replace it with something else, but unfortunately the whole kit revolves around entering it, leaving it, being in a specific one, etc.
We’re already getting the best wish, which is the choice node to not have to cast Stellar Flare anymore. I hope the buffs they made to our normal builders/spenders feel good and we basically can keep a similar vibe to what we have now, but without SF. I’d take that all day over them simply attempting to resurrect Solar Eclipse because “we want it” only for us to be super miserable casting SF to enter it.