I heard that the takan against gerim started in Arab countries that became French colonies. The French repealed the dhimmi laws and accepted Jews into the civil service. The Jews n turn became enamored of French culture. Rich Jews fell in love with French Goyot and tried to use their positions to pressure the rabbanim into performing pro forma “giurim”.
As to minhagim and community, a ger is free to choose so you are not bound by your father’s ancestral customs.