I wanted to come back to this thread to share our experience this past year (note, I am not the OP; this is in response to their post).
My son has been homeschooled since 4th grade due to a desire for accelerated coursework. He has an extensive programming portfolio of graduate-level CS work (but, perhaps notably, did not know about or compete in any of the large national coding competitions that you see referenced in some of these discussions) and has a paid part-time job as a lead developer in his group at an international tech company. His boss wrote a glowing LOR for him. His first two years of highschool (like many others) were disrupted due to the pandemic, but he spent that time working on a family farm, and was able to discuss that in his essays and ECs. Despite that, he had a rigorous transcript. His unweighted GPA was 4.0 (all from outside providers) with 9 AP classes and 3 DE courses at 2 ivy league schools. 1590 SAT, Presidential Scholars Candidate, NMS. Strong essays and we believe his other LORs (from college professors) were strong as well.
He applied to 5 ivies and was rejected by 4 (including Penn, after an initial deferral, where he applied ED and where both parents have legacy) and waitlisted at 1. Brown, referenced earlier as being friendly to homeschoolers, was another one of the rejections.
He also applied to MIT, Caltech, and Stanford and was rejected from all 3. A few other rejections, some surprising, some less so.
He was waitlisted at a few very strong CS schools (UW, CMU, GA Tech, NYU) but the recommendation is not to depend upon coming off any of those waitlists, so we’re not.
He did get into U Michigan Engineering, but his direct entry to CS decision was “postponed” until “early April.” We haven’t heard yet. It seems a little silly for him to attend a school where he’s literally not allowed to major in CS when it’s his passion and he could frankly do it in his sleep, but U Michigan is an excellent school and it’s one of his best options, so it is still on the table.
He was also accepted to RPI and UF (we are in-state for FL), which are both good choices, as well as a few other schools he is considering. It’s not all bad news, and this is not a “feel sad for us” post. We know that all of the schools he was rejected from are a “reach for everyone,” especially for CS, and he is evaluating his options now (he will likely take a gap year to continue working, as he really enjoys his job, and plan to start college next fall). But since you asked about homeschoolers and ivy league admissions, I wanted to share our experience.
I’ve heard a lot throughout our homeschool journey that colleges “love homeschoolers,” and my advice is not to bank on that. If you look at the statistics, at most of these schools, homeschoolers make up less than 1% of their admissions, which is considerably lower than the 2% of high school students who are homeschooled. Based on that, I do think there may still be some bias against homeschoolers in college admissions. Did that affect our applications this year? It’s hard to say of course, but it seems likely that it was at least a factor.
To be clear, we (and most importantly, my son) still feel homeschooling was absolutely the best choice for him, and wouldn’t go back and change that. But I think it’s important to know that college admissions may be more difficult as a result, and to be prepared for any outcome. Apply to safeties, apply to even safer safeties (because a lot of things we think are “safeties” really aren’t), and ideally fall in love with some of them, so if your reaches don’t work out, you’re not heartbroken or scrambling. If I could go back and do anything differently, it would be that: put more emphasis on not just being OK with, but falling in love with and getting truly excited about at least one of our “safer” schools. I think this point in the process would be much easier if we had managed to do that. It is harder to shift gears after all the rejections to get to that point, but we’re working on it. 
Good luck!