Wrong assumption and we all know ‘what thought did’ to borrow a phrase. Perhaps start with looking at the very 1st page of information wrt The Things Network - the Home page: https://www.thethingsnetwork.org/
Where the introductory headline declares:
We are a global collaborative Internet of Things ecosystem that creates networks, devices and solutions using LoRaWAN®
Note “creates networks, devices and solutions using LoRaWAN(r)” - not even LoRa only, (or TCP/IP injection).
If you wish to use the network, and contribute to the Community, then you are welcome to do so - please just use and follow the rules provided to ensure fair use and interop for all…
This work was undertaken in the very early days of LoRaWAN development & deployments, going back to LoRaWAN 1.0 and even pre-release versions, indeed to before the LoRa-Alliance was formally introduced to the market, and long before 1.01,1.02,1.03, 1.04, 1.1 etc. when full GW’s were Very expensive ($thousands!) and more importantly long before the impact on other legitimate full LoRaWAN (Min 8 channel support) users was recognised, diagnosed, and more fully understood. SC implementations were deprecated long before even I started using TTN, several years ago, and have been repeatidly covered and discussed on the Forum since. The Internet rightly hates sensorship and so it is not possible to remove instructions to implement these, especially instructions suggesting how to connect them to TTN, which are often repeated and cloned, nor would one want to as they can have a role, if behaviour well understood and accepted, in small scale private instantiations however they are damaging if used in the Community network.
Indeed and often linked in to the academic year and academic licences for MatLab, etc…
The ‘Integrations & Dashboards’ market is quite wide, with many players and offerings, and very competative, so recommend you take this issue up with Thingspeak or look to use one of their competitors, and dont use their limitations as a reason to impose improper use on the Community.
Re (3) To understand why this is an issue please put the time in to research and read the discussions and historic explainations available through Forum Search.