I'm not talking about politically, but about philosophy or spirit. Compared to the Anglosphere megacities, there is a certain comradeship amongst the French (which you find in other countries, like Japan), a sense of shared fate and community spirit, the idea that this goes before profit and efficiency.
The use of the word communism was deliberately ambiguous and a bit of a pun given the leaning of a sizeable portion of the population in the 20th century. "Commune" means a small town in French, and "commun" can mean "that belongs to all" or "shared".
The French job market is ultra-regulated which makes it relatively rigid with many people left out (and great conditions for the connected). I remember someone interviewing for selling ice-creams - there were 22 finalists! And most graduates will do year-long, low paid internships outside the regulated, cushy full time job system, which like post-docs in US academia can repeat ad infinitum if the economy is bad.
As everywhere else, UberX/Pool allows the marginalised to get an easy job that's a step up from pizza delivery, whilst drastically expanding the market for rides (and I've seen this play in a lot of countries). This is particularly helpful for the numerous people juggling many jobs, and parents (especially single parents) who appreciate the flexibility.
The market was already captured by a single player in France, the worst possible way - in a similar fashion as healthcare in the US. Other markets that have been completely captured by capitalist foreign mega corporations include web search, browsers, social networking, computers, fast food, fashion, real estate supplies, the auto industry (Renault and Peugeot are French only in name at this point)... I guess at least the Rousselet were French?
Perhaps it is time to see things in grey instead of black and white, to avoid labels, to judge companies and actions by their net welfare effect instead of saying "he's not from my team so he's bad" or "she's from my team so she's good" (I'm thinking of you, Democrats in the last election). Almost forgot - reduction in wages? The taxi companies employed many drivers on survival wages (particularly those with difficult immigration situation) and pocketed the difference. Uber's transparency is a net gain for the worker (and the state, which does not get tax-evaded).
UberPop was popular because it allowed people to car pool easily without talking about money, and decongested city centers particularly at rush hour. Enabling widespread, safe car sharing seems to have been perceived as a good thing given the high number of users. I never heard a bad comment about Uber from normal French people (drivers or riders), always from taxi drivers or the news.