Gstr9 annual return

Yes. but not exempted it is optional whether to file or not

Its optional to file. If you have any changes to be made in turnover or ITC you required to file GSTR 9.

Filing of Annual Return ( FORM GSTR-9 ) has been made "OPTIONAL" for FY 2017-18 and FY 2018-19 for taxable persons whose Aggregate Turnover is less than Rs. 2 crores.

So it is OPTIONAL but not EXEMPTED. But it is better to file Annual Return since you can rectify any mistakes caused in FORM GSTR-1 and FORM GSTR-3B.

Details will be taken from GSTR1 & 3B and GSTR9 will be treated as filed

Agree with Suresh Jain. If you do not file your Annual Return on the grounds of turnover being less than Rs. 2 crore, then "it will be deemed to be FILED". Information will be extracted from your GSTR-1, GSTR-2A and GSTR-3B. But the problem is that if any mistake was caused while filing FORM GSTR-1 or FORM GSTR-3B, then your Annual Return also will be filed with those mistake details.