Free licenses always restrict use. You cannot use them without sharing your changes. I don't know what an "Open/free" license is, but if it's your invention, I guess you get to define what a "True" one is.
First, not all free licenses require you to share changes. See, for example, the MIT and BSD licenses. They only require that you preserve the copyright notice, and refrain from suing the original authors.
Second, even the GPL doesn't stop you from using a modified version, just from distributing modified versions without the source code. From the preamble to the GPL "if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received."
The fact that web services don't actually distribute software at all is what inspired the AGPL license in the first place.
Finally, "open/free" refers to the distinction between "open source" licenses as defined by the Open Source Initiative (opensource.org) and "free software" as defined by the Free Software Foundation (fsf.org). As a practical matter, they are similar, but the two organizations have different philosophies.
Free licenses always restrict use. You cannot use them without sharing your changes.
You managed to compress several errors in just two sentences. Free licenses aim to unrestricted use, that's their very reason to be. Search for "software freedoms". You're not forced to share changes, except in very few licences like MPL. Some (not all) free licenses ask you to distribute source for derivative works. Most ask you neither.
Free licenses always restrict use. You cannot use them without sharing your changes.
From section 0 of the GPLv2:
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted
That seems to be explicitly not restricting use, yes?
I don't know what an "Open/free" license is
The Open Source and Free Software people tend to use similar (and often the same) licenses, even tho they don't like eachother and can't agree on anything (or rather they only agree until someone points out that they're agreeing, at which point they start nitpicking on their ideological differences).
Second, even the GPL doesn't stop you from using a modified version, just from distributing modified versions without the source code. From the preamble to the GPL "if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received."
The fact that web services don't actually distribute software at all is what inspired the AGPL license in the first place.
Finally, "open/free" refers to the distinction between "open source" licenses as defined by the Open Source Initiative (opensource.org) and "free software" as defined by the Free Software Foundation (fsf.org). As a practical matter, they are similar, but the two organizations have different philosophies.