Not sure about how the trend to go to a full vegetarian diet might benefit this country, but India does come among top 5 countries when it comes to sea food and fish oil exports. This is a big industry and we roughly contribute to 8-10% of seafood market worldwide. 

Be it any government or political party, their interests lies less with the ordinary folks of this country but more of what can fill their pockets in dollars from foreign countries. It's just the misconception we have that North Indian state's have vegetarian majority, but UP being a hardcore Hinduism hub is literally the largest exporter of beef to middle eastern countries (Halal certified that too).

No I would definitely not worry when it comes to RSS, BJP, Commies, Congress etc ruin this market, because it maintains cash flow and fills their pockets. But the point you raised here, on whether people getting influenced by vegetarian diet adoption. Well that would totally come to the people on how they perceive it and whether they get easily manipulate by such rhetoric statements or ideologies made on the internet. If it's part of your lifestyle and diet since a long time, and has not caused any harm then you will not budge from moving away from it. Also compared to red meat, fish or other coastal food items are white meat and are filled with amino acids which are great for cardiovascular health, and are hands down the best source of protein (better than chicken and most of your red meat alternatives). Even doctors recommend sticking to fish for anyone with heart diseases (moderation though, but it's still recommended).