2015 infiniti q50s 3.7 at 180k miles/ automatic transmission

I have never flushed the trans fluid in my vehicle, but am starting to notice a slight delay in shifting gears and the fact it jumps when shifting between 2 and 3

I’m going to take a look at the transmission and clutch, but before that, I wanted to start simple and check the fluids. I haven’t checked the fluid yet, but infiniti says it is “lifetime” which I have read is true in name only

I’ve been reading that a flush is no good and can actually ruin performance of the transmission, as it may disturb deposits and loose materials. That if I have never messed with the fluids before, to not do it

Is this accurate for a complete drain and fill? I plan on changing the fluid, filter, and gasket completely