I mean. I'd certainly rather be reading or playing video games (or hell, cleaning up around the house or some shit) instead of sleeping, yes. This isn't some kind of tricky consideration, being largely immobile and nonfunctioning for multiple hours straight is a pain in the arse made tolerable only by being unconscious during and (hopefully) rested afterwards.
I'm pretty sure it'd actually be pretty easy to get folks to collectively tell employers to go fuck themself if they tried to encroach on that extra time, too, if that's a concern. Despite all the shit involved with the degeneration of workers rights over the last while in some countries, there's a pretty serious backlash developing against 80 hour workweek bullshit. That wouldn't exactly weaken if you introduced another 8*7 hours of available time to the labor market.
E: Actually, thinking on it slightly more, if whatever solution genuinely managed to mitigate or eliminate exhaustion in the process (and was easily accessed, which would be required for major market disruption anyway), I'd just about guarantee worker mobilization would keep things in line. Two of the biggest roadblocks for low end workers is tiredness and not having enough hours in the day. Cure one with the possibility of curing the other and shit would have to go massively wrong for it to not result in a massive spike in political involvement, involvement with a slant incredibly inclined towards not continuing to put up with exploitative bullshit.