The title is misleading and inflammatory: The article itself is making a much narrower claim about the monetary value (economic growth) derived from equivalent amounts of research effort.
In that context, they claim it takes more effort now than years ago to achieve the same level of economic benefit.
This is far different than anything having to do with the # of "ideas", which is too abstract of a notion to be meaningful the way they use it.
Even if they're correct that it now takes more research to produce equivalent economic benefit, then through one concept of "idea" we actually have more than ever: researchers aren't doing the same bit of research over & over, they're doing new bits. Each bit easily fits into the concept of an "idea", and so in that sense ideas are plentiful, it just takes more of them than before to achieve a given level of economic growth.
In that context, they claim it takes more effort now than years ago to achieve the same level of economic benefit.
This is far different than anything having to do with the # of "ideas", which is too abstract of a notion to be meaningful the way they use it.
Even if they're correct that it now takes more research to produce equivalent economic benefit, then through one concept of "idea" we actually have more than ever: researchers aren't doing the same bit of research over & over, they're doing new bits. Each bit easily fits into the concept of an "idea", and so in that sense ideas are plentiful, it just takes more of them than before to achieve a given level of economic growth.