Avan is never respectful in Sri Lankan Tamil, but used as casual if addressed someone a close friend or relative. I know you are mentioning about the Lankan Cricketer Arnorld, but he is mostly exposed to Sinhalese than of Tamil, hence his Tamil is not good as a typical lankan Tamil, plus his Tamil is mostly like Colombo Tamil, which is a mixture of sinhalese and Tamil
yeah his arnorld ,i forget his name
thanks for clear it about different b/t singalese & tamil