Magic Johnson had the most games with 30+ points and 15+ assists, with 18 games.

who has the most career games with 30 points and 15 assists
Interpreted as:
Who has the most career regular-season games with 30 or more points and 15 or more assists?
JohnsonHardenWestbrookThomasPaulDoncicHardawayJohnsonJamesYoungCurryPaytonIversonStocktonLillardWadeDavisKiddAdamsJordanBealLawsonRondoWilliamsNash18121010977765544433333322222
NAMEGPPTSASTMPGPPGRPGAPGSPGBPGTPGFGMFGAFG%3PM3PA3P%FTMFTAFT%MINREBSTLBLKTOVPF+/-
Magic JohnsonMagic Johnson1859829841.733.28.316.62.30.54.011.719.859.00.71.641.49.211.083.87511494297240
James HardenJames Harden1245218840.437.78.815.71.30.34.711.222.449.84.911.443.110.411.888.04841051545630+124
Russell WestbrookRussell Westbrook1033416238.433.410.816.21.60.85.511.624.447.52.45.345.37.89.582.13841081685524+41
Isiah ThomasIsiah Thomas1034817442.134.83.917.42.90.23.613.823.159.70.61.833.36.68.875.0421392923631
Chris PaulChris Paul930614441.634.05.316.03.30.02.012.321.158.41.83.847.17.68.193.2374483001821+140
Luka DoncicLuka Doncic723211537.433.112.916.41.60.33.411.023.147.54.09.143.87.19.079.4262901122415+41
Tim HardawayTim Hardaway723611545.333.74.016.42.10.32.912.722.057.83.36.451.15.06.379.5317281522018
Kevin JohnsonKevin Johnson724412243.634.93.917.41.90.34.311.117.962.40.30.933.312.314.684.3305271323020
LeBron JamesLeBron James62269644.537.79.516.02.01.53.313.523.058.73.06.347.47.710.275.4267571292018+32
Trae YoungTrae Young51968042.539.26.016.01.00.26.411.623.848.74.29.842.911.813.885.521330513212+24
Stephen CurryStephen Curry51567635.731.23.015.22.40.04.611.221.452.35.811.650.03.03.0100.0179151202310+60
Gary PaytonGary Payton41326141.533.05.015.32.80.52.513.323.855.81.54.831.65.06.083.316620112108+66
Allen IversonAllen Iverson41526148.638.04.015.31.80.33.012.325.847.62.85.847.810.811.891.51941671125+32
John StocktonJohn Stockton41286342.532.03.015.84.50.02.310.816.864.21.01.566.79.511.384.417012180912
Damian LillardDamian Lillard31034740.734.32.715.71.31.05.010.321.348.45.313.041.08.38.796.2122843157+34
Dwyane WadeDwyane Wade3994740.933.06.015.71.31.04.011.020.354.11.02.737.510.012.778.91231843125+52
Baron DavisBaron Davis31034841.334.39.316.02.30.04.011.019.057.93.36.352.69.011.081.812428701212+51
Jason KiddJason Kidd3935044.731.08.316.73.00.35.09.319.348.32.35.343.810.011.785.71342591156+10
Michael AdamsMichael Adams3954839.731.72.716.03.00.04.310.724.743.22.07.726.18.39.092.6119890139
Michael JordanMichael Jordan31004843.733.310.716.03.30.75.310.720.352.50.02.00.012.014.781.8131321021612
Bradley BealBradley Beal2833054.341.510.515.01.51.56.017.034.549.35.012.041.72.54.555.61092133128+10
Ty LawsonTy Lawson2623342.831.03.516.51.00.03.012.021.057.13.05.060.04.05.572.78672066+16
Rajon RondoRajon Rondo2623043.131.06.515.02.50.05.511.020.055.00.52.520.08.511.077.3861350116+8
Deron WilliamsDeron Williams2633142.531.55.515.52.00.03.010.018.055.63.05.554.58.510.085.085114063+36
Steve NashSteve Nash2653343.232.55.016.50.50.05.011.522.551.12.05.040.07.58.093.8861010105+25
StatMuse has game-level data for assists going back to the 1982-83 season.