Everybody is different, but for me the value is in premium cabins to Africa. BA miles are great for stopovers so one can do a pretty great trip to Africa in F for around 1300 per person in surcharges + say $600 total in lost cashback for the 30k spend (and 270k miles iirc).

Now, if you were going to fly coach on a sale fare to JNB or something, it doesn't really compare well. If you prefer to spend the miles on partners it obviously has no value there as well. Also, if reaching 30k spend on a card in a year is a major hassle involving all sorts of tricks, it may not be worthwhile. Lastly, if you want to use it to originate outside of NA or for one-way travel, you can't.

I'd only do the cert if I had a specific plan for the next 1-2 years for travel to a destination where the value is high for you.