Warren might have seemed barely to the left in historic eras. She only seems left now because the recent stretches with the "left" party in control have all been very centrist. Big businesses have been allowed to grow bigger, and organized labor unions have been just treading water federally, as the individual states have been pulling their teeth with "right to work" and "at will" employment laws.
Media consolidation and campaign finance has been driving it. The median voter does not have a reliable, unbiased source of information to drive their decisions, so it's "Garbage In, Garbage Out" politics. Control the inputs to influence the outputs. One faction seems to be experimenting with packing all the main channels with misinformation, disinformation, propaganda, and psyops, and that seems to be worth about 40% of the vote, if the polling is honest and accurate.
The antipodal position to this would be to invest more into public education, independent journalism, legislation penalizing prevarication or material omissions by public officeholders and appointees, anti-secrecy and public disclosure (or "sunshine") laws, and overhaul of broadcast licensing. The issues Warren is focusing on seem more concerned with the flows of money than the flows of information. It's the latter that will produce government reform in a democracy.
Going after Facebook is easy. They're a big, obvious target, and Zuckerberg isn't tremendously charismatic. But Facebook is just one business. Political disinformation is an entire industry.
Besides, this isn't even the question. The OP said that Warren is a middle of the road Democrat. Compared to the positions held by the average Democrat Senator/Congressperson she isn't at all. Whether she'd follow through on those promises when elected is a valid question (though much like Obama, it wouldn't be under her sole control), but that doesn't mean she isn't left-leaning.
How can you trust a candidate who changes platform from progressive to milquetoast centrist so quickly? How can you trust a candidate who said several months ago that she wants to eliminate billionaires, and yet who continues to get major contributions from at least twenty billionaires?
I find it very hard to believe that Warren is genuinely left-leaning. Based on her behavior, it seems to me much more like she is a centrist candidate wrapping centrist ideas in left rhetoric.
> The government needs to be reformed, electing one party or another President isn't going to change much
And pontificating about how "the system is broken" doesn't change anything. There are no actual concrete steps to reforming government that doesn't involve elections and gradual process, or revolution and sudden progress. If you think the latter is in any way likely then you're deluded.