If the beginning weapons of Splatoon 2 were bad or terrible in comparison to the ones unlocked later one, then I would agree that time-gating the weapons is a bad thing. However, the lvl 1 Weapon, the Splattershot Jr. is actually one of the best weapons to use in game. Furthermore, the weapons earned in the first ten levels are considered to be among the best used in the game. The weapons that you do unlock are more about changing up the way you play. Snipers, Dynamo rollers, various-ranged shooters, and different blaster types can change up the way you play. The level cap for getting all weapons unlocked is 30, which is quite a ways away, but isn’t a very steep mountain to climb compared to the level 50.
I think what the devs built this game around is playing it in short bursts of time. Stages are constantly rotating, solo queue modes are quick and snappy to fight through, and matches are relatively shorter than most shooter multiplayer rounds. Even the ranked mode itself forgives losses much more easily than the first game, allowing you to slowly make your way up the ladder if that is your goal.
If the concern is getting money to buy things, then it’s as simple as going to play Salmon Run a few times to get the rewards that either grant you tickets or gives you extra gear that you can sell scrub for money.
There definitely are aspects of Splatoon 2 that are super grindy, probably more than it needs to. The new ability scrub system is extremely expensive and can take a long time to properly get the ability chunks you need. You can decrease the grind a little the week before SplatFests as scrubbing the SplatFest shirt is 10x less expensive, and it’s the most efficient to scrub after getting the first ability due to how EXP scales per level.
I find Splatoon 2 is a lot more relaxing to play. It changes up the the systems from the first game that makes it better to slowly pace through.