Nether portals light if fire is placed anywhere inside its built portal frame. I have seriously considered the idea of building a 3x3 portal for better lighting odds, but ultimately decided that it is not worth it. In this post, we will be talking under the context of a 2x3 wood light portal.
Wood Lighting Explained - #2 by ClearColdWater
in my mind it should be around just (3/2)x faster but then it takes like way more than 5 seconds longer to build. maybe if 1x2 portals were lightable 2x3 portals can be tech xd