No it won't help.
When i started playing Lotro i had a #### pc and a slow connection. Untill late SoM lag issues were ok ish.
After the release of RoI and especially some months later when U6 launched, I had terrible problems to the point I could literally not move while in a 20 v 20 raid (in the moors)
Even some boss raids in pve had skill lag. I remember an instance where you had to spam spacebar to jump at some point, there were times where almost all the raid died cause of 1 second lag...
I don't play Lotro activelly anymore, but I do have a PC built for gaming, and a fast connection, and when I play Lotro just to check things out I'm lagging so much, to the point it feels I'm playing from my old pc and old connection.
In other MMO's I have not yet encountered a single lag spike on my main PC, and playing in the highest possible settings all time...
Hope it helped.
~Nimolas R11 Warden (Retired before RoR) (Snowbourn)
~Eralwen R10 hunter