this give us a yearly inflation around 20% give or take
How can it be?
The number of coins increases every year, and the block reward always decreases.
The yearly inflation must decrease accordingly because the ratio of old coins to the number of new coins increases

It is close. 7344 coins/day is about 0.05595% per day or 20.42175% per year (ignoring compounding).
AEON is only in its third year and as with all normally-distributed PoW coins (not fast-mined/premined/instamined), the inflation rate declines slowly over the first several years. This is by design to ensure that plentiful coins are created and distributed for a significant period of time, and anyone who wants in can get in at reasonable prices, even they are didn't/don't happen to be around at the very beginning.
Inflation will continue to decline to about 1% by the eighth year.