Its to create a psychological perception within your perceived enemy. An enemy who thinks himself isolated generally behaves with insecurity and uncertainty. It also fools him into believing his value is far lower and the enemy can exploit this for greater margins/profits in geopolitical affairs.
The reality is this however, Turkey doesn't need to be Moscow its of no strategic interest. Turkey doesn't need to be London, Paris or Prague, they are again of no strategic interest to Turkey, this can be said for most parts of europe concerning Turkey.
Yet the black sea is of immense strategic significance. Control of the straits between the black sea and Aegean sea is of immense strategic significance/value. Direct access into the northern and south caucuses leading into central asia as well access into Iran and Russia is again of great geopolitical significance.
Access to the balkans is also of value in which part of Turkey sits in.
Control of northern Cyprus is critical to being able to control the eastern med sea and levant, again Turkey owns it and is there. Hence why britian has bases in southern cyprus, its of critical value.
Turkey is also close to the suez and in the future could potential create great problems their for enemy states.
Turkey also has a direct land border into the middle east, the most resource rich region on earth.
This is why the entire worlds powers want to be in the region, whether it be the US, France, Russia, Italy, Germany, England etc.
The Truth is this, a strong Turkey will have the power to isolate many nations from this incredibly important region of the world. What a junction to be in at the point where 3 important continents all meet.
The truth is that geopolitically the enemies of Turkey want to isolate Turkey by changing her borders to give her no geopolitical signifiance, hence why the treaty of sevres looked like. A Turkey that is almost totally landlocked with trapped access into the back sea. Hence cutting Turkey off from all the geopolitical advantages she currently has now.
Hence why a greater armenia was supported by the west, the Azeris destroyed that plot. Hence why a greater kurdistan is being created in syria/iraq, its to cut Turkeys access to the middle east. Its also why the west supports greek imperial ambitions against Turkey. They hope to cut Turkey off from the eastern med.
That sevres map would have removed all of these advantages i just listed, never fall for western fabricated bullshit. They know what they are doing, we should also be wise to the deceivers.