It takes numbers like that to generate enough cash flow to support the position. I don’t think the principle is drawn down, i think the position is supported off the interest.
this probably nets $50-70k per year. The gift is invested and the proceeds are split 3 ways - the annual payout, reinvesting to grow the principal relative to inflation, and a cut off the top to pay the people in the fundraising department. Endowed professorships start at $1.5 to $3M so this seems in the ballpark.
Depends how it's invested, might be even less. If the target return is the same as the UC pension's at 6.75% then I'd assume you'd only want to pay out something like 3-4% each year. It's possibly not even covering the whole position, just supplementing the athletics budget.
As @fugawe09 says, the 1M corpus is not eroded so you only are taking 4-5 % of that annually for “use”. At NC State endowments were tapped at 4% annually, and at one time (maybe 2008-9) some endowed scholarships were frozen due to being “underwater”. Depends on markets and investing strategy to a degree. But the big numbers the public sees doesn’t reflect the actual annual disbursement.