Note that they do impose some additional restrictions for internationals. And yes UEFA also have restrictions on the dimensions of the pitches that can be used for their competitions (Europa League, Champions League, Conference League) much like they have restrictions on stadia at various levels in those competitions. But according to the laws of the game, those are the dimensions.
We both know that a 45x120m pitch would look certainly look weird, but if we are talking about what is allowed in football the standard are the IFAB laws, not what UEFA stipulate for their elite competitions.
In England all organised football is regulated by the FA, so we can say there is no regulation pitch here in England that is less than 60m wide.
To be pedantic though, EUFA defines grassroots football as anything that is non-professional and non-elite, and since 2017 IFAB says that national FAs are free to make their own rules on pitch dimensions for grassroots football. So there is no contradiction - IFAB, EUFA and your FA are all in agreement :)
UEFA regulations are tightly controlled. The pitch must be 100-105m long and 64-68m wide.
FIFA is slightly more lax but that's because FIFA tournaments don't have home and away teams, whereas UEFA do.