I don't know what article you read, but it wasn't the one you posted. Maybe this is why you are so confused by all these options out there
Here is the split right from your 8x8 article:
Sample Routine:
Day 1
Chest
Decline low cable - crossover (touch hands at waistline) 8 X 8
Bench press to neck - 8 X 8
Incline Dumbbell Press - (palms facing each other) 8 X 8
Wide Grip V-Bar Dips - 8 X 8
Biceps
Drag Curl - 8 X 8
Preacher curl (top of bench at low pec line) - 8 X 8
Incline Dumbbell Curl - 8 X 8
Forearms
Zottman Curl - 8 X 8
Barbell Wrist Curl - 8 X 8
Day 2
Shoulders
Dumbbell Side Lateral raise seated - 8 X 8
Wide Grip upright row - 8 X 8
Front to back barbell shoulder press - 8 X 8
Dumbbell bent over rear deltoid lateral - 8 X 8
Triceps
Kneeling rope extension - 8 X 8
Lying Tricep Extension - 8 X 8
2 Dumbbell Tricep Kickback - 8 X 8
Day 3
Back
Sternum Chin up - 8 X 8
High bench two dumbbell rowing - 8 X 8
Low cable row with 18" high pulley - 8 X 8
Medium Grip Lat Pulldown to Chest - 8 X 8
Abs
Double Crunch - (pull in knees and elbows together at same time) 8 X 8
Weighted Crunch - 8 X 8
Lying Bent Knee Leg Raises - 8 X 8
Day 4
Quads
Front Squat - 8 X 8
Hack machine squat - 8 X 8
Sissy Squat - 8 X 8
Leg Extension - 8 X 8
Hamstrings -
Supine Leg Curl - 8 X 8
Seated leg Curl machine - 8 X 8
Calves Standing Calf raise - 8 X 20
Seated Calf raise - 8 X 20
Reminds me of the idiots I see posting online about what a "Killer workout my coach wrote up for me" and then proceeds to post the leg workout which consists of about 50 sets of compound movements (back squat, front squats, bulgarian split squats, hack squat, leg press) and then another 50 sets of isolation work.
Yeah, what an amazing coach. Write down as much shit as they can, so the client really feels it.
A ten year old can write a program full of exercises and sets that will destroy anyone... doesn't mean it's even remotely effective.
Regarding "only" 24 sets a week for biceps and 32 sets for triceps, you realize that in addition to those sets there multiple other sets per bodypart. Also, keep in mind that a lot of people with good arm development only do 3 to 6 sets for biceps and tricep per week? Do you think a tiny muscle like a bicep requires more sets than a large muscle such as your back? And I'm referring to sane trainers here that will do maybe 8 to 12 sets for the entire back (not 32 sets like this program).