I have had one player take expertise in perception so they have +14 at 15th level, which then becomes +15 to +19 with Guidance, usually rolled with advantage.No. The gm need not bump the DC to encounter the 3.5 problems that bounded accuracy was intended to fix. Stock RAW PHB DMG only is enough. Back then you had a situation where some classes vrs some challenges (ie full 1/1 BaB ones & monster ACs became impossible to hit for others (ie fractional BaB ones) if the first set had so much as a chance of missing... The second part of that was in addition if the second group was simply capable of hitting the AC/DC/etc the first group was almost incapable of failure.
5e is designed with all of the DCs set for no expertise & generally for lower level players with lower proficiency bonuses. A character with expertise blows past bounded accuracy both by advancing in levels beyond the narrow band bounded accuracy and by adding double the bonus that is already certain to exceed the math's expectations before getting doubled.
.. Bounded accuracy means that things like expertise and static DCs not linked to levels *can't" exist or that players can't level and all DCs assume expertise
Reigning in expertise to half proficiency would bring that down to +11 and making Guidance grant advantage doesn't stack with the racial advantage, so bounded accuracy is back in the room.