So by your logic, The Evil Dead is a fictional movie within Evil Dead 2's universe because A Nightmare on Elm Street is a fictional film series.

As for your question, firstly, S3 takes place in January-February, 2017. In Season 3, Pablo implies that Kelly has only been away for a few months following Season 2. In 3x01, Brandy says that she will graduate high school in four months; in Michigan, high school graduation happens in late May, suggesting it is currently late January. In 3x06, Brandy says, " A week ago, I was cramming for midterms, and now I'm running from the cops!" High school midterms tend to happen around mid-late January, suggesting it is currently late January or early February. 3x07 centers around a "midwinter" dance, which would fall around early February. In 3x06, Ash states that he is "50-something." A prop for the show places his date of birth on April 8, 1957, meaning this must be before April 8, 2017, his 60th birthday.

Secondly, yes. That does appear to be problematic. Regardless, it's not the first or last time something like this happens in a fictional universe. The MCU currently just pretends the snap never happened. Heck, Agents of S.H.I.E.L.D. did that, and S6 takes place in 2019 on the same exact Earth-199999 timeline. Ignoring that, the main shows and movies don't deal with the consequences except in a few specific instances.

So, really, even though it was huge, why would they bring up something that happened six years ago in the present day plot? Not referencing something is not a contradiction. However, when something IS referenced, such as Ash William's voice or the three books of the Dead, that's an intended connection done to suggest that Evil Dead Rise is part of the same universe as the previous four films. There's honestly bigger contradictions between the first three films than there is between the new one and the TV series, and that doesn't bother anyone because it's just accepted that it's the same reality.

What about Lee Cronin saying he intentionally ignored the TV show when working on Rise since he didn't want to be bogged down by continuity? Or Bruce Campbell saying that he didn't record the voice cameo with the intention of it being Ash?

Evil Dead Rise doesn’t specifically say what year it takes place so it could’ve taken place during the finale of Ash vs Evil Dead. As for Lee Cronin, he didn’t say he retconned AVED, he just said he didn’t want to focus on the mythology it gave us.

Lee specifically said during the press that it took place in the then current year.

Six years passed and we're only seeing an hour and a half of their lives, so not too shocking.

Well the movie doesn’t specify that so it’s the same day as the Ash vs Evil Dead finale.

It's not the same day. Ash vs. Evil Dead's finale occurs in February 2017 while Evil Dead Rise happens in September.

Where did you hear that it was set in September? That forest at the start looks mighty green if it is getting ready to turn to Fall. That, and everyone is dressed like it is still summertime with sunhats and bathing suits.

Bridget was prepping for a Labour Day protest, and near the end of the film, Jessica states that it is going to be "a great weekend" at the cabin, placing the film on the Friday and Saturday preceeding Labour Day. That would be September 1-2, 2023.