I think it's bad accounting to treat all software development as creating capital assets; some of it clearly is, and should be treated as such, although maybe 5 or 15 years is not the right amortization schedule for software.
I like to use the factory analogy - if you're Ford, and you build a big factory to build cars, that's a capital asset, you need to amortize the costs. But the workers inside, making each car? Their wages are expenses, tracked against the revenue of the cars they make. So - if you make a game engine, that'll be used over the next decade or two, that's a capital asset. If you make a game, that'll see 95% of its revenue in the first year, you should be able to expenses the costs (including salaries) of making it.
I like to use the factory analogy - if you're Ford, and you build a big factory to build cars, that's a capital asset, you need to amortize the costs. But the workers inside, making each car? Their wages are expenses, tracked against the revenue of the cars they make. So - if you make a game engine, that'll be used over the next decade or two, that's a capital asset. If you make a game, that'll see 95% of its revenue in the first year, you should be able to expenses the costs (including salaries) of making it.