attacked by data manipulation is consumer trust. with the knowledge that the data is manipulated, consumers are worried, and trust in the exchange decreases. until in the end they transferred their assets to other more trusted exchanges. but I suggest not to save assets on exchange because it is more dangerous
Currently most Exchange plays Volume. this is not an open secret. when it is indeed the attraction of a trader, many see the volume of exchange in the hope that a large movement can give them an advantage. but the fact that there is an exchange itself mostly falsifies their real volume.
usually only a market that has a small reputation will manipulate trading volume and you can better avoid such a place of exchange because the risk of trading in such an exchange is very high.
Sometime websites like coinmarket cap found manipulated values so the only way is to find out by entering into that exchange.
But as you said it won't bring down the total crypto market down because it will such only create temporary effect.
