To be fair, with settings turned to where I normally had them (10 render, fancy graphics, clouds off) I was still getting about the same results so having Optifine provide next to no improvement really, really confused the heck out of me. With this option activated, my fps drops to single digits or at best 10-20 and that's on a render distance of 2 with fast graphics and most other things turned way, way down as to be basically unplayable (outside of the whole lag stuff). The secret to a lag-free experience is to install Optifine and turn off the Terrain animations, since this one option apparently gets applied to millions of blocks at a time (basically everything you see when playing). I don't think Mac/Windows computers are all that different as far as specs go, but I play modpacks for 1.10 and 1.12 with 100-150ish (sometimes up near 200) mods with hardly any lag to speak of (my FPS is consistently in the 150-300 range.)

I have a windows pc from a year or two earlier. And 15/30 mods with no lag and more than 60 fps

Get minecraft for macbook pro