Although I'm a bit scared of the advertisement industry, I'm hopeful this can turn out to be good. Most product placement are very subtle and non-intrusive, so they don't bother me too much. It may eventually lower the price of streaming services because it is a new revenue stream and may possibly enable a service were costumers don't have to pay for, like old non-cable TV but without intervals.
Also, this creates incentives for preservation and re-launch of classic films.
Ideally this could trigger a flow where producers create content; post-producers gather resources from advertisers pay the producers, digitally place products and distribute to consumers. If every step is healthy, it can even get to the viewers without the need to pay for it.
This could be a boom for entertainment in poorer countries where a good deal of the population can't pay for streaming. Some people simply wouldn't mind watching a five year old blockbuster with product placements if they don't have to pay for it.
Of course, it is possible that I'm being optimistic here... we'll have to see how this turns out.