Are Teleconverters A Modern Day Scam?

Are teleconverters worth the hassle? 1.4x or 2x teleconverters give extra reach, but you lose 1 or 2 stops of light, and the image quality goes down. Is it better to just zoom in later in post? Let's test out Fuji 2x tele on the Fujifilm xt4 and 100-400mm for wildlife photography and videography.

If you buy today's gear through my affiliate links, I'll zoom in post 3x and charge myself $800.

Fuji XT4 https://amzn.to/31wORkb or https://bhpho.to/3mXJUs0
Fuji 100-400mm https://amzn.to/3J7Y0jO or USED https://amzn.to/3HZgsJO or https://bhpho.to/3fXB6OQ or USED https://bhpho.to/3tV3VDN
Fuji 2x teleconverter https://amzn.to/3KpXkWP or https://bhpho.to/3OFdXku
Fuji 1.4x teleconverter https://amzn.to/3y3JIxI or USED https://amzn.to/3vSg77R or https://bhpho.to/3KtBHES

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