I think there's a right way and a wrong way to do a remake/remaster. If a game doesn't run well on modern hardware and/or its online features are long gone, a remake can be justified. But to be a truly great remaster, it should also improve upon the original without messing with what made it great.

For example, the Age of Empires remasters were phenomenal, and the AoE2 remaster in particular basically revived the entire series. Not only did it add a fresh coat of paint visually, proper HD/widescreen support, stability updates, and such, there's been a pretty solid stream of new content and extended support. And it wasn't even sold as a full-price title to begin with.

But remakes of games that still run fine on modern hardware, don't really add much of anything new, and are priced at or near full-price? Yeah, cheap cash grab. There's no reason to remake a game less than 10 years old.