>Yes for the common retail person sure, but someone has to purchase stocks to put them into an index. Those are professionals who evaluate PE ratios, profitability, and financial statements.

This is not what an index is. You are describing a fund, but an index fund explicitly does not evaluate PE ratios, profitability, and financial statements, they buy everything in the index according to the market cap. Some proprietary indices are privately curated in the way you describe, but in common use the "index" means all of the companies, rather than a curated subset.