Best telephoto lenses for Canon APS-C Mirrorless?

[thepiecesfit]

So, up until now I've been using an EOS 2000D (Rebel T7) and its 18-55 kit, and I plan on upgrading to an EOS R10 and its 18-150mm kit lens. Even though that lens has reasonable sharpness and zoom range, I'm still looking for some good telephotos for that extra bump in image quality and sharpness, and I was considering these lenses:

-RF 70-200 f/4: seems to have great IQ but not much reach, expensive
-RF 100-400mm f/5.6-8: Cheap, good range, but not sure about IQ
-EF 100-400mm f/4.5-5.6L: Good reach, good IQ, slightly pricey
-Sigma 15-600 contemporary: Seems to have good IQ, but has unreliable autofocus and is apparently prone to breaking
There's also the EF-S 55-250mm which is obviously the cheapest of the bunch but I've seen some planespotters get good results out of that, so I'm considering that too.

If I had to give an example of the sort of image quality that I'm looking for, I think this image captures what I want out of this lens - https://www.jetphotos.com/photo/10891006

Which ones out of these would you guys recommend? Anything that I'm missing?

[AdamT]

The 100-500L has been my go-to lens since I got it!

[sierrafoxtrot]

I started with the 55-250. Awesome lens for the price. I've since moved over to the 100-400 version 2, simply the sharpest lens ever made, and worth every penny.

[NZDN_spotting]

I use the Sigma 60-600. Not as sharp as the 100-400, but very sharp still. Definitely pricey, but 100% worth having that range for what I do. Consider what you need for where you spot.