Ignoring, the issue of Easyjet already having a substantial operation at Lyon, Lyon airport having only 8.5m passengers last year (surprisingly few), and Ryanair having a loathing for French social taxes...
Why would Lyon airport want to actively subsidise Ryanair ? They're in a situation similiar to Manchester. FR makes its big demands (e.g. zero fees), airport publicly refuses to play prostitute, FR goes off in a huff, but FR know that its a big population centre (Lyon was the 2nd most populous French metropolitan area in the 2006 census) and eventually the 2 parties come to an agreement
Then again, there's always the possibility that FR set up an all-year operation at somewhere like Grenoble or St Etienne instead...
Metropolitan Area (France) - Wikipedia, the free encyclopedia