In my latest game, I'm invading the Incas as you can see in the screenshot. I've researched Dynamite, but my units are losing points of movement because the Incas have the Great Wall
.
The reason: Great Wall will become obsolete when the Incas research Dynamite.
I think this behaviour should be changed so that Great Wall never obsoletes but has no effects for any Civ that has already discovered Dynamite.
Of course, the current behaviour has been as it's now in all instances of Civ, from Civ I to Civ V. I think the suggested change would be more realistic but also more difficult to program, and perhaps impossible to mod.

The reason: Great Wall will become obsolete when the Incas research Dynamite.
I think this behaviour should be changed so that Great Wall never obsoletes but has no effects for any Civ that has already discovered Dynamite.
Of course, the current behaviour has been as it's now in all instances of Civ, from Civ I to Civ V. I think the suggested change would be more realistic but also more difficult to program, and perhaps impossible to mod.