Time to move away from awful raster maps and to vector maps?
On my Galaxy Note 2 (2012), you're right. I've ordered a new phone yesterday because it's getting quite bad after five years of daily use.
My girlfriend bought a phone for €300, and the one I ordered (now, a year later) for €250 actually has the same chipset. It runs great on that.
I consider ~250eur to be the bottom of the smartphone market unless you're going for a potato to call and text with (not even browse the web). Given that it runs smooth on that... I'm not sure what you're running OsmAnd on with expectations of fast rendering.
That's ridiculous statement in itself. The bottom of the market are those <$100 china wonder phones, and you have a selection of low-end, but actually branded, devices in the <150eur category. Surprisingly enough, those <150eur devices look like they might be perfectly usable, with specs comparable to my current daily driver (which is couple of years old). As a random example, Huawei Honor 6A [1] currently retails for 99eur around here
[1] https://www.gsmarena.com/huawei_honor_6a_(pro)-8700.php#euro...