Roadmaps are great as they tell us what we to expect from a company in the near future. However, we should still approach them with a bit of caution since not everything that's inside the roadmap is written in stone. Companies often modify their roadmaps as time progresses, and with the current coronavirus pandemic disrupting the hardware world, there's no telling if the alleged AMD roadmap will pan out as planned.
Barring any setbacks, 2022 will be the year that AMD introduces support for DDR5 and USB 4.0 on its desktop offerings. The processors will leverage the Zen 4 microarchitecture, meaning they should retain support for the PCIe 4.0 interface. Don't expect to see PCIe 5.0 for at least another couple of years. The platform will seemingly arrive with native support for USB 4.0 though.
AMD's latest roadmap show that the fourth-generation EPYC (codename Genoa) processors, which will be produced on the 5nm process node, are scheduled for 2022. Things are still a bit blurry on the mainstream side, though. The current Ryzen 3000-series (codename Matisse) is based on Zen 2 while the upcoming Ryzen 4000-series (codename Vermeer) is rumored to be on Zen 3. The reasonable assumption is that the Ryzen 5000-series should exploit the Zen 4 microarchitecture — that is, of course, assuming AMD doesn't roll out anything in between the Ryzen 4000-and 5000-series.
As per Gamers Nexus' information, AMD 2022 APUs will reportedly employ the Zen 3+ microarchitecture, which isn't a big shocker since APUs have always been a step behind Ryzen offerings. Nevertheless, the future APUs will get to take advantage of DDR5 memory, so that's a big plus. It should be common knowledge by now that AMD's APUs excel with fast memory so DDR5 should help maximize the performance on the future processors, especially with DDR5 slating to span up to 8,400 MHz. AMD will allegedly bring DDR5 LP5 support for mobile premium and gaming products, too.
Existing Ryzen 4000-series (codename Renoir) APUs feature the Zen 2 microarchitecture. The next wave of APUs, which we expect to be Ryzen 5000-series, is likely to benefit from Zen 3. The rumored codename for Ryzen 5000-series is Cézanne, in honor of Paul Cézanne, who was famous French artist between the late 19th century and the early 20th century.