I've had all three carriers over the years between my personal phone and my work phone, and switched around a few times. Verizon's "golden age" was the early years of LTE, they struck gold with a ginormous chuck of 700mhz band and were able to put it what felt like everywhere, and made it so you could get signal in parking garages and indoors where the other two couldn't dream of, even if they had less towers in the area like in Portland.You might be right about Verizon sucking and T-Mobile being best in Portland. I was there recently and there were a couple large very populated areas where I got zero reception on Verizon and couldn't so much as send an iMessage. Everyone around me had T-Mobile and had no issues. Very anecdotal, but supports your claim.
But the weird thing is I've gone there a lot over the years to the very same areas, and the last time was the first time I remember having any issues at all.
Fast forward, and 5G changed everything. Their solid LTE network got everyone to switch over, but Verizons 5G network is seriously lacking compared to T-mobiles, and really shows especially in areas of congestion or where they don't have many towers. They put too many eggs in the mm-wave basket, and shot themselves in the foot. T-Mobile focused on mid-band from the jump, and that pulled them way ahead, similar to Verizon's strategy during the LTE days. AT&T has been somewhere in the middle the entire time, both with LTE and 5G. But as Verizon transitions more of their old CDMA spectrum to 5G, they are loosing that edge, because T-Mobile really won the 5G game with all the spectrum they were able to get from Sprints failed wi-max network and smart focus on mid-band with a few years head start.