I believe the outrage isn't entirely unwarranted, but rather than simply scream into the void I believe it is a good idea to reflect upon why some people are annoyed at this decision.
The reason is fairly simple because its all about time. Initially it was fairly rudimentary stuff you'd expect to see, build times, reputation & focus daily caps. Nothing too ridiculous. So time-gates aren't a new thing to Warframe but I believe this current trend started with the Eidolon day/night cycle.
The Helminth system itself
Invigorations
Archon Shards
Steel Path Circuit Grind
Incarnon Adapter Options
When many people began playing warframe, farming a specific piece of gear was all about knowing where it dropped and preparing the gear capable of doing that content. It was pretty simple and straightforward. This means that people who work most of the week could still access that content without having to try and cram an excessively long farming run into a single day of play. Following Eidolons more things have been placed behind time-gates, and while it may not have seemed as prevalent back then its gotten kind of silly now.
For example doing the math on Archon Shards, even taking the pity system into account it will take several years to get five tauforged shards on each frame, even more if the output of new frames goes back to four per year. This heavily extended period of time ignores that one third of the shards acquired would be azure shards which are the weakest of all three types. Now obviously there are other systems or methods of acquisition which may be added in time, but this did make many people rather dubious on new systems. Specifically because time-gates like these are the kind you'd see in games trying to stretch 'content' as much as possible. With newer systems becoming more and more extreme in the span of time required to 'complete' all of it. Now the funny part about Archon Shards is prior people would say 'well you don't need five tauforged shards on each frame' but with the Steel Path Circuit system, now you kind of do, because you don't get to pick which frames show up for that system, and being prepared is extremely important. But I digress
The main issue with the incarnon adapter weekly cycle is that it forces people to wait multiple weeks or over a month (now) to get a weapon they either missed out on prior, or didn't choose the first time around. This frustrates people who put aside time, probably on their limited time off, to work toward this goal. Now obviously the time-gate in this instance is to keep the content 'active' because if people are trying to get the 'next' incarnon they will keep logging on to grind through it. However there is one key issue with how it is being done if the intent were simply to make sure the content wasn't instantly farmable you don't need a weekly cycle, you just need a weekly time-gate to farm two adapters.
What I mean is rather than have specific weapons listed each week (thus time-gating people who want a specific weapon for several weeks to a month+), you could've simply offered two adapters of your choice per week.
This way people who work and people who have excessive time to play both benefit, and at the same time, your content remains active.
Now I'm sure there will be an ocean of replies saying 'but then people will only farm the good incarnons' and that is true, but all you have to do to solve for that is make all of the incarnons good. DE has the usage/acquisition data for incarnons, and I'm sure they can figure out which ones need help over time. If all of the incarnon options available are good most players will go after them, and the content will remain active.
Its a win win. It also makes adding new incarnon options later on extremely easy, as you won't need to say, code a weekly reset to change gear options.