Суммируйте значения в повторяющихся строках с помощью Bash

Это будет работать независимо от того, может ли какое-либо из полей в кавычках содержать , (например, если какое-либо из полей с текстом-заполнителем "Page Title 1" на самом деле было чем-то вроде "I, Robot - Page 1"):

$ awk '
    BEGIN { FS=OFS="," }
    NR==1 { print; next }
    { num=$NF; sub(/,[^,]*$/,""); sum[$0]+=num }
    END { for (key in sum) print key, sum[key] }
' file
url,title,tag,version,guide,views
"https://website.com/2-2/section/product/page-title","Page Title 2",tag-2,"2-2","guide-2",5
"https://website.com/4-4/section/product/page-title","Page Title 4",tag-4,"4-4","guide-4",7
"https://website.com/1-1/section/product/page-title","Page Title 1",tag-1,"1-1","guide-1",115
"https://website.com/3-3/section/product/page-title","Page Title 3",tag-3,"3-3","guide-3",60

Один из способов использования GNU datamash:

$ echo "url,title,tag,version,guide,views" && datamash --header-in -st, -g1,2,3,4,5 sum 6 < input.txt
url,title,tag,version,guide,views
"https://website.com/1-1/section/product/page-title","Page Title 1",tag-1,"1-1","guide-1",115
"https://website.com/2-2/section/product/page-title","Page Title 2",tag-2,"2-2","guide-2",5
"https://website.com/3-3/section/product/page-title","Page Title 3",tag-3,"3-3","guide-3",60
"https://website.com/4-4/section/product/page-title","Page Title 4",tag-4,"4-4","guide-4",7

Или с awk:

$ awk -F, 'NR==1 { print; next }
           { groups[$1 "," $2 "," $3 "," $4 "," $5] += $6 }
           END { PROCINFO["sorted_in"] = "@ind_str_asc" # Sorted output when using GNU awk
                 for (g in groups) print g "," groups[g]
           }' input.txt
url,title,tag,version,guide,views
"https://website.com/1-1/section/product/page-title","Page Title 1",tag-1,"1-1","guide-1",115
"https://website.com/2-2/section/product/page-title","Page Title 2",tag-2,"2-2","guide-2",5
"https://website.com/3-3/section/product/page-title","Page Title 3",tag-3,"3-3","guide-3",60
"https://website.com/4-4/section/product/page-title","Page Title 4",tag-4,"4-4","guide-4",7

другой awk

$ awk -F, -v OFS=, 'NR==1 {print; next} 
                          {v=$NF; NF--; a[$0]+=v} 
                    END   {for(k in a) print k,a[k] | "sort"}' file

url,title,tag,version,guide,views
"https://website.com/1-1/section/product/page-title","Page Title 1",tag-1,"1-1","guide-1",115
"https://website.com/2-2/section/product/page-title","Page Title 2",tag-2,"2-2","guide-2",5
"https://website.com/3-3/section/product/page-title","Page Title 3",tag-3,"3-3","guide-3",60
"https://website.com/4-4/section/product/page-title","Page Title 4",tag-4,"4-4","guide-4",7

Пояснение
вывести строку заголовка; сохраните значение (последнее поле), уменьшите количество полей, чтобы оставшаяся часть записи стала ключом ($0), добавьте значение в аккумулятор с ключом (суммирует эквивалентные значения ключа). В конце выведите ключ и значения и отсортируйте.