The last paragraph is almost definitely about Valve:
"And here we are. I spoke of my return to this shore. It has been a circuitous path to lands I once knew, and surprising to see how much the terrain has changed. Enough time has passed that few remember me, or what I was saying when last I spoke, or what precisely we hoped to accomplish. At this point, the resistance will have failed or succeeded, no thanks to me. Old friends have been silenced, or fallen by the wayside. I no longer know or recognize most members of the research team, though I believe the spirit of rebellion still persists. I expect you know better than I the appropriate course of action, and I leave you to it. Expect no further correspondence from me regarding these matters; this is my final episode."
No more HL2:Episode N coming, the development team is too different.
"And here we are. I spoke of my return to this shore. It has been a circuitous path to lands I once knew, and surprising to see how much the terrain has changed. Enough time has passed that few remember me, or what I was saying when last I spoke, or what precisely we hoped to accomplish. At this point, the resistance will have failed or succeeded, no thanks to me. Old friends have been silenced, or fallen by the wayside. I no longer know or recognize most members of the research team, though I believe the spirit of rebellion still persists. I expect you know better than I the appropriate course of action, and I leave you to it. Expect no further correspondence from me regarding these matters; this is my final episode."
No more HL2:Episode N coming, the development team is too different.