I guess this also fits this thread: Unfinished Business was the beginning of the decline over the quality of the original show. 
Not sure this is a 1+1=2 case.
Scheduling also changed...the big decline in ratings may have correlated with losing a valued time slot.
RachelLeVega was referring to the overall quality of the show, i.e. the editing, tasks, and what not, not quantity.
But I have to disagree, RachelLeVega. TAR 18 still had that charm of the TAR 12-17 seasons (the India episodes still hold up really well IMO).
I think TAR 20 was the last really well-crafted season in terms of editing.
Here's an unpopular opinion: TAR 25 is the worst season in terms of editing. So much footage left out 
And it hasn't really gotten better since...
27's editing was much worse than 25. Remember most of the shining moments of teams (e.g. Kelsey and Joey argue) was found in the extra videos online instead of the actual episode. The only good episode in terms of editing was the Macau one.
The thing that pisses me off with the current
editing of the show is how they cut out traveling and pre-destination/location hype scenes because it gave the teams a real sense of character and breathed life to the destinations they were traveling through (as you were mentioning with Kelsey and Joey arguing). Even if the music wasn't too adrenaline pumping, the pioneering and rising seasons still showed the journey aspect of a high-stakes race successfully and memorably. There have been some stand-out episodes of the post-20 seasons, but a majority was because there was some big moment or outside force affecting how the editors had to format the episodes. Leg 2 of TAR17 was straightforward and nothing of team drama, but it still delivered with the thrill of traveling and the race that I still remember fondly and excitedly to this day (Brook's knack to sell sunglasses, Michael managing his own at the sunglasses, the Ghanian women being so random toward the racers, a dude wanting to buy Mallory's entire pad of glasses, the dangerous taxi race between the choir boys and docs for just 7th! and 8th! near the end, and I still remember tearing up for Andie & Jenna's early demise) whereas more recent episodes felt out of tune from the race aspect of the show for omitting small, but very telling moments like these from the broadcast and not showing the journey over the destination. One team I love to mention who got an "unfortunate" edit from this is Kerri & Stacy. On the episodes, they were bubbly and motherly - just that. On the extras, they were a total 180: very outspoken, mechanically smart, and let's just say Brenchel weren't the only ones who disliked Vanessa & Ralph with flying colors.
For me, I prefer when all the teams have their starring moments on the race and not just the several who make it farther than leg 4. I appreciate and love season 16 and 20 more for this reason alone. If you make the show, you deserve to at least have some kind of personality and story arc shown of you and your team which many recent early-eliminated teams, unfortunately, did not.
