I am on my third LG big screen since 2017...all excellent, especially the new 77" OLED-CX. NONE allow the HBO MAX app (nor HBO GO, etc. previously). So, I purchased a 4K Dolby Vision Firestick (for HBO GO in January 2019). Worked well. Then, HBO says, "No GO, only MAX." Firestick says, "No GO for MAX." WTF? After chatting with HBO customer service for nearly an hour, we realize there are "corporate complications." With MAX struggling to launch, Firestick was allowed to keep GO going until they could handle MAX. In the meantime, I still wanted MAX and all the extras for the same price as GO. So, I choked hard and purchased an AppleTV 4K 8GB Dolby Vision unit. I hate Apple, but, I have got to admit, it is sweeter and smoother than the Firestick, with a much more elegant interface. Both units want to sell you shit, but you can mentally filter that out. I watch on the AppleTV (you get the AppleTV+ streaming service free for a year...Ted Lasso is FUN! - other good shows, too). Of course, six months after buying the Apple, Amazon worked out things with HBO/Warner and now the Firestick accommodates the MAX app. I still prefer the Apple experience (and I wish I didn't).
Note: I have ALL the streaming services and HBO is still the king of the premium TV series. However, all those great legacy shows (available both a cable subscription (ick) and from MAX (GO had 'em, too) are in HD - 5.1 ONLY. Fine looking and sounding, but old news. With HBO MAX, they are taking it to the MAX - new movies and shows are in Dolby Vision and Dolby Atmos. Compressed, yes, but it shan't be too long before we get uncompressed streams (maybe at a higher price). If you have a system like mine (13 discreet audio channels/amps/speakers), properly placed and set-up...with uncompressed DV & DA, no current movie theatre competes, as they have to entertain hundreds of guests, compromising their systems. I have seen hundreds of films on a real IMAX (Irvine/LA) and full-blown Dolby Theatre (best all-around - IMAX* has harsh, Klipsch-like horns, poorly placed.). They just can't compete with an OLED Big Screen and high-end home audio.
Thus, if you really want HBO MAX (and you won't regret it), and you can afford the AppleTV, get it. Else, wait until the next Prime Day (if you have Amazon Prime), and get the 4K DV Firestick on the cheap.
*Visually, films shot in IMAX 70 mm on IMAX cameras (especially 3D like Polar Express), are second to none (Nolan had his own techs set-up and run Dunkirk on the Irvine, CA IMAX - OMG!)