First off Holmes was really not on Foremans radar by the Young fight which took place in early 1977. Holmes was just an up and coming hwt yet to beat any top five contender. There was no reason to "avoid" Holmes at this point in time. In his second career beating an old Holmes would have added nothing to Georges all time ranking. Losing a decision to Holmes could have wrecked his comeback.
Not for me, unless he came back somewhere near Holmes peak and rolled him but even then i'd like a tad more. Holmes took quite a while to get his due as a top fighter, if Foreman beat him at any early to middling stage he would not have got full credit for whom he'd actually defeated. Foreman needed more wins for mine. That loss to Jimmy Young at his peak was bad. It adds a lot of question marks. The war with Lyle is also less than convincing for me. Lyle had been beaten in two of his previous three fights. Foreman showed great heart but he also went life and death with a guy others weren't. If he came back around the time Holmes beat Ali, beat Holmes and then had a handful of defenses or more i would have him 3 at worst. He wouldn't even need the later comeback, which i don't rate as highly as some. He was absolutely young enough to come back around this time and even potentially defend for a few years. Apart from Holmes the division was very weak and full of underachievers. If he could get past Holmes the sky was the limit as guys like Weaver, ****ey, Shavers, Spinks, Snipes and co were not likely to beat him imo. Heck, old Foreman may have beaten some of them i'd reckon. I'm a long way off the beaten track and deep into fantasy land here with myriads of intangibles and if's and but's but it's interesting to speculate. As a matter of fact i might even dedicate a thread to a similar scenario just to see how far off base i may or may not be. The big thing tho in all of this is that i would favour Holmes to beat him. That's a pretty big roadblock.