It doesn't need any more, when export BOM, you can chose which attribute as you want

@UserSupport I see, thank you, but the problem is that for my already existed projects with "In BOM" attributes previously added to some components , if I add attribute with the same name for new components then it doesn't show value in the Export BOM, because it seems decides that it is two different columns but it shows only initial one and doesn't seconds one and doesn't add values from the seconds one into the column.

@UserSupport No it does. If I want to specify 2 supplier part number options now I have to go around clicking parts individually and adding new fields. This can get tiresome, especially if you have a large number of instances of the same part, whereas if the "In bom" option were available I could have just added it in the one row in the BOM and it would have gotten applied to all the instances. Or I have to export the BOM and add it manually, but that's asking for trouble because if you make any changes in the EDA and miss updating the BOM to reflect it, you could end up with a huge headache. It's so annoying when devs decide to hastily remove features just because they're providing an alternative, could just as easily have left both options.