Turns out it has been 10 years since the last Castlevania release and 15-16 since anything that could be considered mainline

2008 - Castlevania: Order of Eclessia

2009 - Castlevania: The Adventure ReBirth

2014 - Castlevania: Lords of Shadows 2

And yet, Castlevania doesn't have an air of being in a ditch unlike other legacy series. Hell, Metal Gear feels more forgotten about despite MGS 5 releasing on 2015. Maybe it was because of the netflix show or due to how the older titles are remembered or because how omnipresent the term metroidvania is.