The thing about Gaming Laptops is that they are hardware all packed into one portable small frame, which affects the pricing.
Over the past years as Mobile GPUs became more capable of running games well at High settings or better, they've become much more attractive for one that would want a portable gaming solution, for example.
Personally I see that Laptops for gaming can be categorized into at least 3 categories:
The $500 tier
The $1,000 tier
The $1,500+ tier
The $500 tier tend to not have the best gpu, at best a 4 GB GPU, on average a 2 GB GPU be it NVidia or AMD. For light gaming or running games that aren't graphics intensive, they can serve one's needs just fine, esp. if one is into emulation IMO.
The $1,000 tier is where the decent stuff is but at the same time, this price is twice that of a console, however certain laptops within this price range can last one for over 5 years esp. if they have a GPU with 6 GB (though some may have 4 GB such as having a GTX 16 series GPU). Coupled with a good CPU and RAM, they could run some modern games decently. IMO one could set up such a laptop as the gaming/media center for multiplayer games and emulation, etc.
The $1,500+ tier is where the really better hardware are, but again, due to them being put into such a compact design, their price is pretty high. This tends to be the 'ideal' price for laptop gamers (like me), but the cheaper the better. If one looks up some $1,500 priced lappies or ones around that price point, they'll find some lappies from a few years ago which would still be effective media/gaming center for a wide variety of games.
Non the less, I agree that normal PC building allows for one to swap out parts and upgrade and then resell those old parts or repurpose them for someone else to use while bearing in mind the limitaiton of the old parts.
...and that's the thing about gaming lappies; if you know their limitations you can decide on what you want to play on them and possibly make the best use of their capabilities.
Not sure we'll ever see dirt 5 in a bundle EA owns them now and they don't like bundles.
...........
Hmm I could get the game + all current dlcs for $30....GMG could offer this discount again in the future.
...and Forza Horizon 4 is releasing soon....