In a resume, I want to see where you've worked, how long you were at each job, and your major accomplishments at each. Those can be technical and non-technical -- perhaps you made some excellent people process improvements you can showcase. I don't want to see your hobbies or where you went to high school, keep it professional and relevant to work. Personally, I use LinkedIn as my resume. If a recruiter wants something different, they're welcome to use print mode or format it in Word / PDF themselves.
I don't care about your GitHub profile. It's a small value add, nothing more.
Ageism is not a thing I've seen. I've worked at a trendy unicorn and was involved in hiring multiple people 30+ and at least one 50+. I'm in my mid 30s.
At your level, I really want to know how you work with others and influence teams across an organization. Your tech skills are now secondary to your people skills, but you still have to be up to date on tech since you'll be one of the driving forces at the company.
Why don't you want to rely on your network to set you up in the future? It's one of your biggest professional assets and will open doors to jobs that aren't publicly advertised.