Any argument that...
Please stop. I've now cited an official government source, and a reputable international source. Both of these analysis were done by a team of economists, nuclear engineers, and accounted for as many factors as reasonably can be taken into consideration. You have cited... absolutely nothing.
That the oceans contain enough uranium for 10,000 years of once-through energy production is well known and easily confirmed. The IEEE Spectrum article cites current research results that indicate the cost of seawater extraction can be performed at a cost of about $300/kg, a price point that the uranium spot market has already broken in the past, and the additional cost added to electricity by paying $300/kg vs current prices of around $100/kg is only about 0.6 cents per kwh still quite competitive with coal, gas and renewable energy sources.
Economists making government resource projections aren't permitted to consider emerging (aka unproven) technologies. Up until now there has been little incentive to try to develop seawater extraction (more expensive admittedly) as long as conventional mines were cranking out adequate supplies at low prices. This will change, and new technologies developed and exploited.
Just look at fracking. No production to speak of 10 years ago, now production is climbing steadily, soon to create a large gas surplus. Or renewable energy, with double digit increases in wind and solar power year after year. New technology and production processes with lower costs aren't limited to gas, solar and wind - uranium extraction benefits also. New processes often do not get perfected until there is economic demand for them.