It's been attempted several times, but parts go in and out of stock all the time between the various vendors that it's hard to get a single-source list of parts. So, a list would probably be outdated in a week.

The best you can do is make a list of part numbers, but that too can change as old parts become unavailable and are substituted with newer/alternate parts.

I know Arrow has and perhaps Digi-key also has a BOM upload ftp section of their web site where you can list your part numbers with the corresponding mfg part number and if there is an EOL update you will get a notification. I even got an EOL notification recently for a part I had purchased from Digi-key, but did NOT even look to see what it was for.
I actually worked on the ftp site for Arrow about 19 years ago so I'm sure theirs has come a LONG way since then. Back then they were trying to do it as a fee for service feature, I have no idea if it would still be that way.
Further Ed at GPE G-P-E often announces things like EOL and quality issues right here in river city, you might want to pick his brain about this.

This happens all the time in the audio hobby and in the audio forums. You can build it in excel and upload to Mouser, DigiKey and similar. All the vendors let you know if the part is out of stock or obsolete. They also provide replacement part numbers. This happens all the time now because of lead-free parts replacing the parts with lead.

Great idea and I'm all for it.

HHaase and barakandl (as well as others) do various boards already, they may have some words of wisdom for you also.