Yes, more than ever, individual stock prices move based on the market on any given day. While this has always been the case, in the past it was more of a traders’s behavior, ie bad news happens, people start selling in a herd.
Now, in addition to that, there us a mechanical cause built in to the market which assures this will be the case. ETFs are index funds which can be traded like stocks. Because of their internal structure dealing with the creation and destruction if shares based on demand (which works well as long as there is good market liquidity), as the ETF price rises it falls, they directly drive the price of the stocks they hold.
So on any given day, at an individual stock level, there us more likely to be a problem with the efficiency of the market.
This could be a good thing for traders working on a more long term basis. But for intra-day trades it will certainly make life more difficult.