They may be right about one thing - GDP will go up. Not in short term, but in the succeeding year. There will be a dip in the short term, which will form a smaller base for the next year to reflect. So, if the GDP growth goes down to, say, 6.5%, then it will be a smaller base.
If I earn Rs. 100 this year, Rs. 90 next year and again Rs. 99 in the second year, the second year's growth will be at 10%.