Ive got a 2019 Street glide with the M8, coming from a 2003 Road king , does yours have fly be wire throttle ?

Nice!

and Yes, mine is throttle by wire.
I think Harley started doing this right around 2008 depending on the model of bike.

Affirmative, all 2008 and up Harley touring models are TBW.

Softail got TBW in 2016.
Dyna got TBW only on the 2016 and 2017 FXDLS Low Rider S with the 110".
Other Dyna's in 2016 and 2017 were TBC. Then they got the Axe.
Sportsters? I don't mind them much.

This is across the board, special bikes in those model families such as the CVO's and whatnot may of got TBW earlier than above.
Harley is super consistent across the board. NOT
As shown with the Dyna situation.

No Hijack,