I guess it has more to do with how they behave and solve issues at the end of the day. With telcos you feel assured of a "professional" team to deal with your billing, maintenance, technical help.
Cable operators in my locality used to oversell, show speedtest only to their server and then makeup all sorts of excuses for ping/speed drop to any other server, used to ignore my calls incase something happened.
And the worst part I used to pay him for 6 months plan but he never had enough balance in his account to topup my id so he used to add 1 month plan to my account. (I got to know this once he logged into log2space from my computer), and due to this i faced atleast 2days of no internet every 30 days even after paying
So atleast with any big brand (telcos or even ACT, Excitel, OneBroadband etc.) we dont have to face such petty issues