Necromancer is still very potent, if not more so if you include the create magen spell, and works with the Tasha summons spells rather than an and/or situation.
Same issues are in play but it hasn't lost any ground with just destroying the action economy.
Jein. The issue with "endless hordes of minions in a computer game" is frame rates and lag. As it turned out, skeletal hordes also slow up computer games. A lot of games with necromancers have backed off the idea of "endless hordes of minions" in favor of more managable summons and thematic powers (e.g., blood, life, death, shadow, curses, etc.). One could summon tons of minions as a necromancer in Guild Wars 1 and Diablo 2, for example, but the necromancers in subsequent games generally have (if any at all) 1-6 minions, including golems. That said, I also have these later games in mind when I say that I have found that players coming into D&D expecting to play a video game style necromancer are often disappointed with D&D's typical version.