Maybe what you've said is correct. The people might've lost interest on the ODI format as it is more time consuming than the shortest format of T20 and T10 format cricket.
Yes this is valid point, Cricket fans showing more interest. towards t20 rather than ODI. spans of life change and in this fast paced world people have short time and love to attend short time matches for entertainment.
it is just the starting and more matches left. Maybe as time passes the ground will get filled. Same time I've never seen a opening match with empty seats as it happened with England vs New Zealand. Not just because people have lost interest, but BCCI hadn't shown interest in making World Cup great than ever. Not having an opening ceremony is not for saving money, it is a way to prioritise IPL.
The same things happened with Asia cup where lot of empty seat in the first opening match but we have seen a great audience in the last matches. It is not true to crictism BCCI for this. Total 48 matches to be played and fans love to watch qualifiers match more than the opening matches
What an inining played by Kusal mendis, hit 8 sixes and 4 fours in his 76 runs inining. unfortunately he couldn't able to make century. This type if batting is set in the india pitches otherwise you cannot win the matches. Markram scores in the same way able South Africa to give high target. Srilanka lost 3 big players and looks like South Africa will now easily win this match because all hard hotter goes to pavilion.