I personally wouldn't. They had some very good games for their national team and clearly are USMNT legends.
However, none of those players ever excelled at an elite level at the club level. In my mind, to be world class you excel for the best clubs in the best tournaments in the world. Excelling for your national team in the best tournaments in the world is strongly recommended but can be overlooked if your club performances are just other worldly. Club football dominates the calendar and if you aren't at an elite level there, I don't see how you can be considered world class because that's where the bulk of the assessment is made.
The highest Keller ever got was 1st choice for a mid-table Tottenham team for two seasons. He never played for an elite club.
I actually think Friedel could have performed for an elite club if his opportunity had come in say, 2005 when he was excelling for Blackburn. Unfortunately, his opportunity came before Blackburn and he was very underwhelming at Liverpool. Had things worked out differently, I think he could have proven himself at the elite club level. But it's hard to say he was world class on the back of being a Blackburn Rovers legend.
Howard came the closest. He did better at Man United than Friedel did at Liverpool but ultimately, neither succeeded when tasked with being the #1 for a club expected to challenge for league titles and make deep Champions League runs. Similar to Friedel, I don't think you can say Howard was world class strictly on the back of being an Everton legend.