in 2020, most Smartphones launched aren't as big improvement over predecessors like it happened in 2019 maybe because of Covid-19 losses and manufacturers are waiting for a wider 5G roll out so everyone joins the bandwagon instead of holding on to phones that are good enough but 4G for longer.
Samsung:
Note 20 non ultra with a plastic back? seriously Samsung Gorilla glass victus, 6,5,4,3+, ceramic you used in S10 and you chose polycarbonate for your most premium phone?
Oppo:
From Reno 2 to Reno 3 Pro Oppo lost OIS and Snapdragon 730G, and in Reno 4 Pro axed telephoto camera as well and from 64MP to 48MP camera and bought back SD 720G (Identical performance to 730G of Reno 2)
F15 with same chipset as last year's F11
A92 lost Dolby Atmos and Gorilla Glass in favor of 1080p Display of A9 2020. again, no chipset upgrade
Vivo:
Launching same specs again and again in different designs. Vivo S1 has no definite successor
Realme: Current C series (11, 12, 15) doesn't compare in performance with C3's G70 processor. 6 Series is a good upgrade but now falls into a price slab above realme 3 or 5 sseries.
Xiaomi: Xiaomi seems to be doing well in terms of specs / pricing but build issues (dust in lens of redmi 9 series), software bugs (proximity sensor and wifi) and ads
in 2019 every midranger started coming with 128 Gig storage, funky motorized cameras, chipsets that pushed decent performance and some good fast chargers coming in box.
2020 is like yes we upgraded to Amoled display but downgraded this and this, lowered build quality and materials used for only 10 percent increase in price from last year model.