If you have a shelf full of Henson DVDs, you're probably not in the target market for a Disney streaming service. IMO, the target profile probably falls along these lines:
- Adults in 20s / 30s
- Kids age 1-13
- Never had cable/sat, or cut the cord long ago
- Do not have large DVD or blu ray library
These are the people who were raised on Disney (parks, clothing, stuffed animals, etc.) and view it as something worthwhile to share with their kids. But they don't have cable, thus limited access to Disney Channel and every other network that would show Disney films. And they haven't bothered to invest in discs at $20 each.
In my opinion, there are plenty of people who fit this profile that would be willing to pay $8-10 per month for access to a huge library of Disney content. And the market will only grow as today's teens start their own families, all with a 21st century attitude toward media consumption.
Disney has been running a service like this in the UK for some time now, so I assume they have some idea of what consumer response to expect.
Lastly regarding the dig at Disney IT, it's streaming services are run by MLB Advance Media which is a complete separate entity from any other Disney operations. Disney was previously 1/3 owner of MLBAM and is in the process of purchasing a majority share. MLBAM runs streaming operations for Major League Baseball, ESPN, PGA, NHL, HBO and many others. They are a well-regarded leader in the field.