I think the finicky part is the indexing system, the old friction shifters were way more reliable. On an indexing shifter any knock on the rear mech can bend th

I think the finicky part is the indexing system, the old friction shifters were way more reliable. On an indexing shifter any knock on the rear mech can bend the hanger and mess up the shifting and it can't be adjusted without straightening the hanger. A good indicator of a bent derailleur hanger is that adjusting works on one part of the cassette but than causes issues on the other end. On a friction shifter it doesn't matter, you can always make adjustments by hand. Internal hubs are heavy, drag like mud and usually require twist shifters.