Nashville SC today released mounds of information about season tickets heading into the club’s first year in its purpose-built soccer stadium after two years as a tenant in the Tennessee Titans’ Nissan Stadium. Here are the price points for the various season-ticket packages:

Big D Soccer helpfully compiled Supporters Section prices across the league prior to the 2020 season. For new members, $340 for the season ($306 for those who are First String members – season-ticket holders prior to the 2021 season) puts the pricing on the very cheap end.
Quite honestly, the high-end doesn’t seem cheap per se, but it certainly looks on the more-reasonable end within the league. FC Cincinnati’s highest price point is $53, Sporting Kansas City (one of the teams with a more-expensive price point for Supporters Section tickets) has prices as high as $65 in non-premium sections, etc. Nashville’s a more-expensive town, but to sit anywhere other than midfield, pitchside… you’re getting in pretty reasonably.
NSC’s Season Tickets site has far more details about the whole picture of season ticket memberships.