Upwork also skews towards one-off gigs for businesses serving a tiny audience, often with <=$100 pay. The average full-time, long-term job offering could be equivalent to maybe 50 average Upwork jobs (just a ballpark number I pulled out of nowhere).
And let's assume your pulled from nowhere ballpark number would be true. Even then the percentage of those jobs would still be in favor for PHP, with PHP being an order of magnitude higher than Ruby
