Count the match you're getting, and the match you're not.

• The match is a share of what you put in, up to a share of pay, per the tiers you pick. Real plans add vesting schedules, per-paycheck matching (true-ups), pay caps and yearly limits.
• Growth: the yearly match is added monthly at a constant return; with a raise, pay and the match grow once a year.
• Every number is hypothetical and depends entirely on what you enter. Small changes in assumptions can change results a lot.
• Returns are smooth and constant in the single-number projection; real returns vary every year, and real markets can do better or worse than anything shown.
• Inflation is a single constant rate you choose (except in historical replays, which use the actual CPI of each year).
• Growth compounds monthly (or at the contribution frequency) and contributions are made at the end of each period.
• No taxes unless you turn on the simplified tax drag (all positive growth taxed each year at your rate, which overstates tax for buy-and-hold). No fees unless you set one.
• Inputs stay in your browser. Saving uses this device's local storage; a share link contains the numbers you entered, so anyone with the link can see them.

Coteau may be wrong. Check every number yourself, and talk to a licensed professional before acting on anything.