The figures seem consistent with most sources:
- A Lazard 2018 study puts nuclear firmly in that range.
- A UK government study puts new nuclear construction at 95 GBP per megawatt hour, which sits somewhere in the middle of the range stated by Reuters, depending on the exchange rate of the day.
- The OpenEI configurable chart trends lower, but only outliers lie below the bottom of Reuters' stated range.
There appears to be a fair amount of agreement on the figures in question, across a number of countries and governing bodies.
Speculation - accounting for fuel disposition after use and decommissioning the plant at end of lifetime adds substantially to the low marginal cost-per-MWh during operation. On top of this, it's hard to think of any utility project with higher up front capital costs than a new utility-scale nuclear power plant, and that factors into the lifetime generation costs as well.
This isn't to say that nuclear might not still outperform the fossil fuel plants (particularly the dirty ones like coal) if their externalities (cleanup, pollution) are taken into account, but it's easier to do cost estimation for nuclear plants because their storage and decommissioning costs are well established at this point.