Those changes wern't made untill the forced multiplayer had "become a huge success", by being forced on people...You speak the truth.
I too find the idea that it was 'forced' a little strong.
ME3 sold around 3.5 million copies worldwide.
About half of those people played the multiplayer, some 1.7 million people.
You might say that half of people not playing the multiplayer shows lack of support for it.
Yet only 42% of purchasers had finished the single player within 5 months of release
Also looking at the MP manifest, about 800,000 people look to have played multiplayer enough to get their war assets improved and no more.
A further 900,00 look to have played... and played... and played.
I think it would be fair to say that multiplayer was indeed forced upon you because of the war asset calculations.
But to imply its success was tainted in some way misses the point in my opinion, as it fails to recognise not far off a million people who played well beyond the single player game requirement. Many of those players logged literally several hundreds of hours in the game.