I’m of the opinion that semi pelagianism and Arminianism stem from pelagianism
Semi pelagianiasm and Arminianism are not synonymous.
At least Arminianism in the classic sense.
Total depravity is affirmed under classical Arminian teaching (I'm talking Arminius himself here, and Wesley) while limited atonement and unconditional election is not.
Election is conditioned on saving faith, but such faith is given by the Spirit, it's not something human beings have.
I know it's common and popular for many Reformed / Calvinists to want to lump everything else under some form of Pelagianism, but it's in actual fact not true. It's true in certain circumstances (I'll admit a lot of Arminians are semi Pelagian) but it is not theologically true when you actually look at the details.
There are really four degrees of choice:
A. Augustinian (Calvinist essentially)
B. Semi Augustinian (Arminianism)
C. Semi Pelagianism (Eastern Orthodox)
D. Pelagianism (liberal thought, Finney, etc. mostly)
I've no idea where the Catholics truly sit, but I'd venture to say it's probably a little complicated.