Sindee, thank you for your answers. From them and your OP comment that you have to sit very far forward on the seat and you try to keep your shoulders squared, I assume you are small of stature. If that is the case, it appears to me that when you purchased your RT-L, you were asked to fit yourself to the Spyder and not the other way around. At this point, because of the age of my Spyder and my size, I was in the exact opposite situation, a tall bloke who needed more leg room. Because of that, I intentionally purchased a BRP Spyder Comfort Seat that gave me the leg room I needed, but immediately introduced the second half of the fitting the bike to me problem; being 2+ inches farther back was going to have the handlebars too far forward. For my model year of RT, BRP also had a very widely adjustable optional handlebar system called Tri-Axis bars, so I added them to the OTD deal. Those bars are not made for 2023 RTs.
Here is the key to how I set the Tri-Axis bars to fit my riding posture. I sat on the bike, closed my eyes, and extended my arms to a starting point where I felt my arms and hands would be comfortable. I then opened my eyes and saw how I would have to adjust the bars, first fore and aft so the grips were right where I wanted them in my palms; and second, raising them to where they came up to where they touched my outstretched palms.
The first two months or so in my new Spyder I fiddled with the bar adjustments after almost every ride, and I never made adjustments more than 1/2" at a time. That's how I adjusted the handlebars on the bikes when I began riding in the 1970s, exactly the same way. Now, here's the rub you face and that I am unable to help with because I have absolutely no idea what variety of bars exist for the 2023 RT Limited, either from BRP or aftermarket manufacturers. Another part of the rub is as I understand the available bars may have holes drilled in them in which pins for the L and R handlebar control assemblies are inserted to maintain their proper orientation. Do you need handlebar risers? I don't know; they could simply be another method of trying to fit you to the Spyder. Are you getting weak? I am not able to say; only you can make that determination. As you can see from my avatar, physical fitness has been a large part of my life and well into my ninth decade I continue to exercise daily, so I'm in the best condition for long distance motorcycle touring. Good luck.