It's hardly surprising, now is it? DOSBox offers a whole lot of options that old DOS didn't have, so for the uninitiated it can be a bit daunting (as could real DOS, of course). Some things are easier with DOSBox (having enough memory available, for instance, sound card support etc), other things are more difficult (output method, scalers etc).
DOSBox has been able handle anything I threw at it but sometimes with a lot of tweaking. If a game comes with DOSBox and a preconfigured dosbox.conf, that should take out the inconvenience for these players. If there is a surprise for them it will be that DOSBox runs the game well as it was configured by GoG, and that using it that way is not an inconvenience.
Seems to me like what GoG will be doing is provide the actual game with all the updates from the original vendor and wrap it up in a neat installer. Rather like a frontend with a profile set up for the game. Nothing you couldn't do yourself if you fished the game out of the bargain bin at your local software store, but it doesn't seem like they're charging exorbitant amounts of dough for it either. Sounds fine to me.
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