You are right that both Maruti and Hyundai are launching new models in the market at this point in time. Businesses exist for the long term and normally they do plan for expansion even in the midst of a downturn. In fact, some of the best strategies are crafted by companies in the midst of a downturn. 

Currently, the auto sector has gone into a slowdown and that is borne out by numbers. July marked the eighth successive month when the YOY sales of passenger cars slowed down. In fact, the fall of 31% in sales in the month of July 2019 was the worst performance since December 2000. The slowdown has been driven by a number of factors. The liquidity crunch in the aftermath of the IL&FS crisis has made consumers wary. A Credit Suisse study pointed out that consumers are now willing to postpone their purchases by as much as 1 year. The sharp rise in fuel prices has also been a reason as has the rise in insurance costs of a car. Lastly, NBFCs, that normally fund cars, are facing a liquidity crisis and higher cost of funds. That has also slowed sales of cars.

Last week, Maruti chairperson, R C Bhargava, announced that Maruti will go ahead and expand its sales push despite the slowdown. Most carmakers realize that India continues to be a big market and a market with great potential. Creating good and solid ideas in a downturn will surely help them to handle the downturn in the auto sector and push market share in the long run. That probably explains why Hyundai and Maruti (they together account for 18 of the top-selling models in India) are continuing to expand in an aggressive manner.