>>4133688Get the longest lens you can with the highest pixel density body you can. The 100-400mm+GH6 combo isn't a bad choice but it's stupidly expensive and doesn't even have an integrated teleconverter.
Any 20MP MFT is nearly as good for reach and you can have them much cheaper.
But if you want max bang for your buck, get a 90D and a Sigma 150-600mm (the EF lens with RF adapter kit, for some reason it's currently cheaper than just the EF lens, you can even sell the adapter to further lower your costs)
>Sigma 150-600mm f/5-6.3 DG OS HSM Contemporary Lens with Canon RF-Mount Adapter Kit>$899>Sigma 150-600mm f/5-6.3 DG OS HSM Contemporary Lens for Canon EF>$989>EOS 90D>$119990D is a reflex but it also has dual pixel autofocus, so it has all the advantages of reflex and all the advantages of the latest generation of mirrorless (fast live view AF) in one camera. And it doubles as a telescope even when turned off. Grand total, $2098. You could also get a Nikon P1000 but the quality won't be even close. It's just $996 so it's tempting, though. All these prices can go lower if you buy used, something worth doing.
>>4133694Yeah and then the camera shits its pants because it's a toy. And a 150-600mm for Fuji costs $1999, plus the camera itself that costs $1699. $3698 total, for 6% more reach, about 90% less durability and 150% less joy (when joy goes into the negatives it's suffering).