I completely agree with you that the flagship phones of the past years are far better quality than the new mid-range phones, but it should be considered that the Galaxy S9 and S10, as well as the iPhone X and 11, After 5 years since the introduction, Their batteries may need to be replaced and soon they will encounter problems in terms of software.
Tenho um A05s que celular espetacular, oq mais impressiona e o custo beneficio ele é muito barato, mas entrega muita coisa q intermediários não entregam.