I don’t like not having numbers so I hopped on my 116 Pally.
At 259 ilvl (heirlooms) he has 44,960hp and 1997 strength
At 263 ilvl (azerite) he has 57,700 hp + 4861 absorb trait and 2,398 strength.
That’s a 1.5% difference in character ilvl but a 28% loss in effective health (57,700+4861=62561) and a 16.7% decrease in strength
I currently have 41 120s & 3 @ 110+ & a newly minted Zandalari @ 23 so I have a good idea of how long it should take to level. I’ll have to keep a close eye on my xp/hr the rest of this week since I just now finished Timewalking on all my alts this is the first chance I’ve gotten to level and once I started getting smashed I came to see if anyone else was experiencing the same thing.