Actually reason might be the Live Telecast processing fee which is levied by government which increases the expenses incurred by the concerned sports broadcaster for making the event available on their channels. More so Australia Vs West Indies won't attract advertisers to even recover the transmission cost which is applicable hence has been kept as OTT Exclusive
Since this event is outside india, no question of processing fee for WPC. Even if they go for ott only in future, still they have to pay to WPC as per existing rule, when event is in indiaThis could be a major reason for absence of major sporting events on TV in the coming future. With the onset of 5G, i beleive OTT is the only way forward.