IMO it is wise to honor the "fog of war". I am pretty sure UK intelligence is doing it's best to make an unbiased estimate of Russian losses. The use of satellite data can be invaluable for some of the estimates, but the reality is neither the UK nor the US has direct oversight of the battlefield. Both must, to some extent, get data from Ukrainian sources.
It is universally true that in the vast majority of battles, lost or won, the casualties/equipment losses are over-estimated. This is most often not because the reporting troops are TRYING to make things look better than they are. It just "happens" for many reasons. Nobody in history so far has been immune to this problem, despite many attempts to minimize the errors.
All that said, even if the 300k number is wrong by a factor of 3, there have been a LOT of Russian casualties. Undoubtedly the Russian government is doing all they can to suppress any truthful reporting of casualties. Both Russia and Ukraine have resorted to infantry heavy warfare, and that kills/injures lots of people. Russia has repeatedly spent troops recklessly, as if they are a limitless resource. As Russia is finding out, they are not. Russia has a population that would support greater mobilization. It does not (yet) have the political will to do so.
Ukraine OTOH has always been quite aware of their numerical disadvantages. They have minimized losses as best they can. Right now, Ukraine is saying next year will be "key" to winning the war. That may be (at least partially) because after that point they expect to be out of troops for offensive operations.
Let's all hope the 300k is somewhat accurate and that the Russian population "finds out about it". That might end the madness. Otherwise, Ukraine will have to "roll the dice" once more. We (the west) will need to do all we can to help them succeed while they still can. I unfortunately have little confidence that the US and the EU are going to do anything like that. Lets hope that what they do actually do will be "enough". IMO the consequences of a Russian victory in Ukraine are dire. That would have been somewhat true even if the US and the EU had done a Chamberlain and washed our hands of it, but we didn't. We made it partially "our" war. Arguably, that was the "right thing to do", but we now have to win it. The public and the politicians doesn't seem to understand this. Indeed, "failure is not an option".
It is universally true that in the vast majority of battles, lost or won, the casualties/equipment losses are over-estimated. This is most often not because the reporting troops are TRYING to make things look better than they are. It just "happens" for many reasons. Nobody in history so far has been immune to this problem, despite many attempts to minimize the errors.
All that said, even if the 300k number is wrong by a factor of 3, there have been a LOT of Russian casualties. Undoubtedly the Russian government is doing all they can to suppress any truthful reporting of casualties. Both Russia and Ukraine have resorted to infantry heavy warfare, and that kills/injures lots of people. Russia has repeatedly spent troops recklessly, as if they are a limitless resource. As Russia is finding out, they are not. Russia has a population that would support greater mobilization. It does not (yet) have the political will to do so.
Ukraine OTOH has always been quite aware of their numerical disadvantages. They have minimized losses as best they can. Right now, Ukraine is saying next year will be "key" to winning the war. That may be (at least partially) because after that point they expect to be out of troops for offensive operations.
Let's all hope the 300k is somewhat accurate and that the Russian population "finds out about it". That might end the madness. Otherwise, Ukraine will have to "roll the dice" once more. We (the west) will need to do all we can to help them succeed while they still can. I unfortunately have little confidence that the US and the EU are going to do anything like that. Lets hope that what they do actually do will be "enough". IMO the consequences of a Russian victory in Ukraine are dire. That would have been somewhat true even if the US and the EU had done a Chamberlain and washed our hands of it, but we didn't. We made it partially "our" war. Arguably, that was the "right thing to do", but we now have to win it. The public and the politicians doesn't seem to understand this. Indeed, "failure is not an option".