I, in Australia, had never received a spam call or SMS, until two years ago. I now receive several per day. All automatically blocked, but still.
My number was leaked in a particular data breach that actually had nothing to do with me, but a different family member who had all of their contacts vacuumed up before the breach. So from my perspective it was passive.
in india its pretty common for businesses/ orgs to sell number data in bulk which is bought by advetisers.
you can be sure to be bombarded with calls and sms if a students applies for a notify thing or gives their number somewhere outside exam halls or on student help websites.
same for shops asking for mobile numbers.
then there are marketers who randomly call each number, send sms to see what sticks.
the situation is pretty bad i would say because for every careful person who sees through the ruse, there are hundreds who fall for million dollar prizes and kyc scams and all.
people call you and say "we are form bank. main branch. you need to verify your debit card or your account will close". no name of bank, no place of branch, just "from bank. main branch".
My number was leaked in a particular data breach that actually had nothing to do with me, but a different family member who had all of their contacts vacuumed up before the breach. So from my perspective it was passive.