I agree with this. However, this would be quite an undertaking and would have to be database-driven (SQLite, MySQL, etc.). Take, for example, an LM386 audio amplifier IC.
There are at least 3 variations of that IC, each with its own electrical characteristics. That would require at least 3 entries in a "part lookup table", with the "primary key" for that table being the MPN. Each user will have different opinions on exactly what to name that field (MPN, MFN, etc). as well as which data fields (from the data sheets) that need to be associated with that part.
Then, to be truly useful, there would need to be a vendor lookup table which would include not only the MPN, but the vendor part number and vendor price as well, along with various other data fields that each user will also have different opinions on.
MUCH time then would be spent just doing database maintenance tasks. While not impossible, it would be very time consuming to say the least. And with the varying opinions on exactly which data fields need to be included for each lookup table, I feel it would be nearly impossible for all users to come to an overall agreement on this.
Just my thoughts. Anyone else... Feel free to jump in here with your thoughts.