Well Animated and Prime aren't that old so, no use in pandering to that demographic with nostalgia since the toys are still out there for anyone to collect, even if pricey, they're still easily found and also it's likely the fans of those aren't in the "man i'm old and have a disposable income let me blow it on nostalgia" age range. Beast era has had shit peppered in through the years but has gotten stuff lately for serious collectors who are willing to pay for it
All the anime stuff is kind of frowned upon by most fans, so hate to say it but you're just shit out of luck because most people don't like that stuff so I doubt it will ever get HEAVY amounts of pandering outside of fan favorite things getting thrown out there like Armada Starscream or the recent Prime. Car Robots....Skybyte and Scourge are probably the only characters who hold enough weight in fans to ever get anything again.
Beast era is tricky because it was such an anomaly and oddity, it fits in with nothing else so it's harder for cross generational fans to accept, someone might buy a non G1 Starscream if it doesn't look like him just because it's him, and vice versa, they can make up their own headcanon. Beast Era stuff only caters to a very specific group of fans that doesn't connect with any other era, so it's less profitable to focus on I would imagine...also, I feel it gets love, not as much as rabid fanboys would want, but it's been getting peppered in through the years like I said at a fair pace for something that's considered obsolete by the corporate company putting this shit out who doesn't give a damn, I mean we just got MP Megatron and I'm sure more on the way