To expand on J. A. Streich's answer:
By ignoring material components, you are increasing the power and versatility of spell casters. Of course, D&D is a game where the rules say you can change the rules, so you are free to make the rules what you want, and what you think is fun.
You asked if it is significantly more challenging or cumbersome to use this feature. Consider three cases:
Find Familiar
The material components are 10 gp worth of charcoal, incense, and herbs that must be consumed by fire in a brass brazier. 10gp is a significant cost to a first level character. The brass brazier is also perhaps a challenge. It isn't even listed in the equipment list in the PHB. So acquiring the components requires at least a stop in a suitable store, and perhaps work to find such as store. However, if you ignore the components, a first level character can cast find familiar right out of the gate. Either option is fine, but they are definitely different.
Continual Flame
The material components are ruby dust worth 50 gp, which the spell consumes. Ignoring the material component allows the caster to cast it at will. In some campaigns, having light underground is a challenge to be overcome. If this spell is free, it is easier to overcome the challenge. Either option is fine, but they are definitely different.
True Resurrection
The material components include 25,000 GP of diamonds, which the spell consumes. The presence of the component helps to make death-reversal magic a possibly rare commodity. Of course, since true resurrection requires at least a 17th level caster, it is already limited, but the presence of the costly component means that even well-intentioned NPC casters can reasonably ask PCs for a significant outlay in order to use the spell. Either option is fine, but they are definitely different.
So, yes, using the material component rules is significantly more challenging and cumbersome, in certain cases.
You ask how others incorporate components.
I expect players to adhere pretty close to the rules. For most material components, they either have to have the component, or have to use an arcane focus. For consumable components, they have to acquire them specifically. For death-reversal magic, the cost is situation-dependent; in other words, they don't actually know how much it is going to cost until they try to cast the spell.
As they advance in levels, I allow them to hand-wave a fair amount of trivial stuff. A first level caster needs to acquire the components for find familiar specifically. A tenth level caster with lots of gold can be assumed to have stocked up at some point in the past.