A2A | GEE ImageCollection filter not working on a property

Question

Tried to filter an ee.ImageCollection using a property value but it is not working.

I have an image collection named my_col that I created using the map function. Although I have added one 'year' property to every image that the map function returns, and casted the year value explicitly as a number, like this:

// this is what the function is returning
return ee.Image(0)
         // more processing
         .set('year', ee.Number(ee.String(current_year_name)));

When I later use a filter to display the image of year of choice, it doesn't work:

Map.addLayer(my_col.filter(ee.Filter.eq('year', 2020)), viz_params, 2020);

But treating the year property as a string worked:

Map.addLayer(my_col.filter(ee.Filter.eq('year', 2020)), viz_params, '2020');

It is strange that the filter isn't working even after explicitly casting year as a ee.Number but whatever works works!?