They might decide to rewrite an lgpl project, but there is a massive sunk cost. At the point they make the decision the gpl project is less tempting to bring fully in house.

  (L)GPL:
  - Investing $3M to extend.
  - Would cost $17M and 3 years to re implement to baseline and then extend.
  - Lose all community development inputs because new solution  is fully in house.

  Permissive:
  - Investing $3M to extend.
  - Would cost $0 and 0 years to keep in house and still extend
  - Keep 100% of community development inputs initially and potentially forever if they are able to extend in a way that avoids conflicts.  Can port most community developed features with some effort.

Corporations make decisions 1 quarter and at most 1 year ahead. It's a very hard sell to say "we need to take 3 years and a huge investment to get to where we already are at". It could happen for some very specific, high value technologies where someone at the Sr. Director or VP level is taking a long view , but it would be extremely rare.